Tosa Ken
Tosa Ken Dog
Tosa Ken Dogs
Often referred to as the canine equivalent of a sumo wrestler, the Tosa is a guardian breed from Japan. He was originally a fighting dog, taking part in highly ritualized but silent combat. Characterized by a massive head, a wrinkled face, and impressive size, he has strong protective instincts and the power to enforce them.

The Tosa, as he is nicknamed, is a giant breed, weighing 100 to 200 pounds. Bulldogs, Mastiffs, Great Danes, and Japan’s own Shikoku are all said to be in his background. In the United States he is generally a companion or show dog, but in Japan he can still be found in the fighting ring.

Few people are equipped to live successfully with a Tosa. He is not an appropriate choice for an inexperienced dog owner. The Tosa has many good qualities, but he is not the easiest dog to live with. If you want the calm, confident dog that is the Tosa at his best, be prepared to do a lot of homework to find him and put in plenty of effort training and socializing him once you bring him home.

The Tosa is large, powerful, fearless and intelligent. With his family, he is quiet, watchful and protective. He is aloof towards strangers but isn't usually aggressive toward people. To shape those qualities, he needs a leader who can guide him with firmness and consistency and without using force or cruelty.

Other dogs would be wise to give the Tosa a wide berth. He can be aggressive toward dogs he doesn’t know, especially those of the same sex.

Begin training as soon as you bring your Tosa puppy home, while he is still at a manageable size. That 20-pound puppy will quickly grow much larger. The Tosa is gentle and willing to learn and responds well to positive reinforcement techniques such as praise, play, and food rewards. It’s always a good idea to take a Tosa to puppy kindergarten followed by basic obedience class, especially if you are working with a trainer who understands the Tosa mindset.

Early, frequent socialization is essential to help prevent a Tosa from becoming overly suspicious or fearful of anything new or different. Purchase a Tosa puppy from a breeder who raises the pups in the home and ensures that they are exposed to many different household sights and sounds, as well as people. Once your vet gives the go-ahead, continue socializing your Tosa throughout his life by taking him to puppy kindergarten class, visits to friends and neighbors, and outings to local shops and businesses. This is the only way he can learn to be discriminating, recognizing what is normal and what is truly a threat.

The Tosa is best suited to a home with a large yard surrounded by a solid fence that is at least five or six feet high. This is a territorial breed, and he must learn his boundaries. Do not rely on an underground electronic fence to keep him contained. The shock it provides won’t necessarily deter him from leaving the yard if that’s what he wants to do.

Like any dog, Tosa puppies are inveterate chewers and because of their size can do more damage than puppies of some other breeds. Don’t give them the run of the house until they’ve reached trustworthy maturity. And keep your Tosa puppy busy with training, play and socialization experiences. A bored Tosa is a destructive Tosa.

Chaining a Tosa out in the yard and giving him little or no attention is not only cruel, it can also lead to aggression and destructive behavior. While it’s good for the Tosa to have access to a fenced yard, he should live indoors with his family.

Other Quick Facts

  • The Tosa is the canine equivalent of Japan’s sumo wrestlers and is often depicted in ceremonial costume.
  • When you look at a Tosa, you see a large, powerful dog with a large, broad head, boxy muzzle, wrinkled forehead, medium-size ears that hang down, brown eyes and a short coat in a deep, solid, rich red, fawn, red and black brindle, brown, black with red markings, or pied. Some Tosas have a black mask or black-tipped hairs. The body is slightly longer than it is tall, and the tail is thick at the base, tapering to a tip.

The History of the Tosa

Based on written records, the Tosa has been known in Japan for almost 1,000 years. He originated on the island of Shikoku at a place called Tosa Wan, from which he takes his name. Courageous and tenacious, he made his name as a fighting dog.

The earliest Tosas were spitz, or Nordic, dogs. When Western breeds were introduced to Japan in the 19th century, however, the Tosas were bred with mastiff- and bulldog-type dogs to increase their size and strength. The “new and improved” Tosas became renowned for their fighting ability.

The onset of World War II nearly brought an end to the breed. The island nation had difficulty feeding its people, let alone 150-pound fighting dogs. A few were hidden away on the island of Hokkaido so they wouldn’t be killed, and they survived until the end of the war, when keeping them was no longer illegal.

The United Kennel Club recognized the Tosa-Ken in 1998 and classifies it as a guardian breed. The Tosa is not recognized by the American Kennel Club but may compete in AKC companion events such as obedience trials.

Tosa Temperament and Personality

Due to his breeding as a fighting dog, the Tosa is not a good choice for the novice owner and, perhaps, not the best choice for an experienced owner. The Tosa has a strong propensity to show aggression toward other dogs, and managing this characteristic may not be well-suited to a typical suburban neighborhood. He is normally a peaceful, well-mannered dog with his family, and is very devoted to them. He is wary of strangers, but isn’t usually aggressive with people. He is a fearless protector and guardian. He is intelligent and fairly easy to train due to his biddable nature. Use positive reinforcement techniques with him to take advantage of his desire to please his owner.

The Tosa can be good with the children in his family when raised with them, but rough play should be avoided around him because it can stimulate his fighting instinct. He is not a good choice for families with small children due to his massive size. Babies, toddlers, and small kids can be knocked over accidentally.

The Tosa is slow to grow up and oftentimes doesn’t mature until about 4 years of age.

Training should begin right away for the Tosa puppy. Even at 8 weeks old, he is capable of learning good manners. Never wait until he is 6 months old to begin training, or you will have a bigger, more assertive dog to handle. 

If possible, get him into puppy kindergarten class by the time he is 10 to 12 weeks old, and socialize, socialize, socialize. However, be aware that many puppy training classes require certain vaccines (like kennel cough) to be up to date, and many veterinarians recommend limited exposure to other dogs and public places until puppy vaccines (including rabies, distemper and parvovirus) have been completed. In lieu of formal training, you can begin training your puppy at home and socializing him among family and friends until puppy vaccines are completed.

Invite people to your home, too, so he becomes accustomed to visitors. These experiences as a young dog will help him grow into a sensible, calm adult dog and help minimize his wariness of new experiences.

Talk with a reputable, experienced Tosa breeder. Describe exactly what you’re looking for in a dog, and ask for assistance in selecting a puppy. Breeders see the puppies daily and can make uncannily accurate recommendations once they know something about your lifestyle and personality. Choose a puppy whose parents have nice personalities and who has been well socialized by the breeder from birth.

What You Need To Know About Tosa Ken Health

All dogs have the potential to develop genetic health problems, just as all people have the potential to inherit a particular disease. Run, don’t walk, from any breeder who does not offer a health guarantee on puppies, who tells you that the breed is 100 percent healthy and has no known problems, or who tells you that her puppies are isolated from the main part of the household for health reasons. A reputable breeder will be honest and open about health problems in the breed and the incidence with which they occur in her lines.

Like many large and giant breeds, the Tosa can develop hip dysplasia and may be prone to gastric torsion (bloat). Ask the breeder to show evidence that a puppy’s parents have OFA or PennHIP clearances for hips. Having the dogs "vet checked" is not a substitute for genetic health testing.

Careful breeders screen their breeding dogs for genetic disease and breed only the healthiest and best-looking specimens, but sometimes Mother Nature has other ideas and a puppy develops one of these diseases despite good breeding practices. Advances in veterinary medicine mean that in most cases the dogs can still live a good life. If you’re getting a puppy, ask the breeder about the ages of the dogs in her lines and what they died of.

Remember that after you’ve taken a new puppy into your home, you have the power to protect him from one of the most common health problems: obesity. Keeping a Tosa at an appropriate weight is one of the easiest ways to extend his life. Make the most of your preventive abilities to help ensure a healthier dog for life.

The Basics of Tosa Grooming

Grooming the Tosa is fairly straightforward due to his short coat, though his large size means it’s a big job. A bath every three months (or when he’s dirty) in a mild vet-approved dog shampoo is a good idea. Brush his sleek coat with a natural bristle brush or mitt once a week. Use coat conditioner/polish to brighten the sheen. Wipe out his facial wrinkles with a damp cloth and dry them thoroughly to help prevent skin fold infections.

Check the Tosa’s ears every week and clean them if they look dirty. Trim toenails once a month. Regular tooth brushing with a soft toothbrush and doggie toothpaste will help keep the teeth and gums healthy. It is essential to introduce grooming to the Tosa when he is very young so he learns to accept the handling and fuss peacefully.   

Finding a Tosa Ken

Whether you want to go with a breeder or get your dog from a shelter or rescue, here are some things to keep in mind.

Choosing a Tosa Breeder

Finding a good breeder is a great way to find the right puppy. A good breeder will match you with the right puppy, and will without question have done all the health certifications necessary to screen out health problems as much as possible. He or she is more interested in placing pups in the right homes than making big bucks. Be wary of breeders who only tell you the good things about the breed or who promote the dogs as being “good with kids” without any context as to what that means or how it comes about.

Good breeders will welcome your questions about temperament, health clearances and what the dogs are like to live with and come right back at you with questions of their own about what you’re looking for in a dog and what kind of life you can provide for him. A good breeder can tell you about the history of the breed, explain why one puppy is considered pet quality while another is not, and discuss what health problems affect the breed and the steps she takes take to avoid those problems. A breeder should want to be a resource for you throughout your dog’s life.

Avoid breeders who only seem interested in how quickly they can unload a puppy on you and whether your credit card will go through. Breeders who offer puppies at one price “with papers” and at a lower price “without papers” are unethical. You should also bear in mind that buying a puppy from websites that offer to ship your dog to you immediately can be a risky venture, as it leaves you no recourse if what you get isn’t exactly what you expected. Put at least as much effort into researching your puppy as you would into choosing a new car or expensive appliance. It will save you money in the long run.

Lots of reputable breeders have websites, so how can you tell who’s good and who’s not? Red flags include puppies always being available, multiple litters on the premises, having your choice of any puppy, and the ability to pay online with a credit card. Those things are convenient, but they are almost never associated  with reputable breeders.

Whether you’re planning to get your new best friend from a breeder, a pet store, or another source, don’t forget that old adage “let the buyer beware”. Disreputable breeders and facilities that deal with puppy mills can be hard to distinguish from reliable operations. There’s no 100% guaranteed way to make sure you’ll never purchase a sick puppy, but researching the breed (so you know what to expect), checking out the facility (to identify unhealthy conditions or sick animals), and asking the right questions can reduce the chances of heading into a disastrous situation. And don’t forget to ask your veterinarian, who can often refer you to a reputable breeder, breed rescue organization, or other reliable source for healthy puppies. 

The cost of a Tosa puppy varies depending on the breeder’s locale, whether the pup is male or female, what titles his parents have, and whether he is best suited for the show ring or a pet home. The puppy you buy should have been raised in a clean home environment, from parents with health clearances and conformation (show) and, ideally, working titles to prove that they are good specimens of the breed. Puppies should be temperament tested, vetted, dewormed, and socialized to give them a healthy, confident start in life.

Before you decide to buy a puppy, consider whether an adult Tosa might better suit your needs and lifestyle. Puppies are loads of fun, but they require a lot of time and effort before they grow up to become the dog of your dreams. An adult may already have some training and will probably be less active, destructive and demanding than a puppy. With an adult, you know more about what you’re getting in terms of personality and health and you can find adults through breeders or shelters. If you are interested in acquiring an older dog through breeders, ask them about purchasing a retired show dog or if they know of an adult dog who needs a new home. If you want to adopt a dog, read the advice below on how to do that.

Adopting a Dog from Tosa Rescue or a Shelter

The Tosa is a rare breed and it is unlikely that you will find one at a shelter or through a breed-rescue group. If you wish to try that route, however, here are some tips to help you find and adopt the right dog from a rescue group or shelter:

1. Use the Web

Sites like can have you searching for a Tosa in your area in no time flat. The site allows you to be very specific in your requests (housetraining status, for example) or very general (all the Tosas available on Petfinder across the country). AnimalShelter can help you find animal rescue groups in your area. Also some local newspapers have “pets looking for homes” sections you can review.

Social media is another great way to find a dog. Post on your Facebook page that you are looking for a specific breed so that your entire community can be your eyes and ears.

2. Reach Out to Local Experts

Start talking with all the pet pros in your area about your desire for a Tosa. That includes vets, dog walkers, and groomers. When someone has to make the tough decision to give up a dog, that person will often ask her own trusted network for recommendations.

3. Talk to Breed Rescue

Networking can help you find a dog that may be the perfect companion for your family. You can also search online for other Tosa rescues in your area. Most people who love Tosas love all Tosas. That’s why breed clubs have rescue organizations devoted to taking care of homeless dogs. Search online for Tosa rescues in your area.

4. Key Questions to Ask

You now know the things to discuss with a breeder, but there are also questions you should discuss with shelter or rescue group staff or volunteers before you bring home a dog. These include:

What is his energy level?

How is he around other animals?

How does he respond to shelter workers, visitors, and children?

What is his personality like?

What is his age?

Is he housetrained?

Has he ever bitten or hurt anyone that they know of?

Are there any known health issues?

Wherever you acquire your Tosa, make sure you have a good contract with the seller, shelter or rescue group that spells out responsibilities on both sides. Petfinder offers an Adopters Bill of Rights that helps you understand what you can consider normal and appropriate when you get a dog from a shelter. In states with “puppy lemon laws,” be sure you and the person you get the dog from both understand your rights and recourses.

Puppy or adult, take your Tosa to your veterinarian soon after adoption. Your veterinarian will be able to spot problems, and will work with you to set up a preventive regimen that will help you avoid many health issues.