The Tosa breed originates from Japan and is also known as the Japanese Mastiff. It is a large-sized and robust dog who is known for courage and patients as well as a very balanced temper.

The breed was developed to be a protector and is known as the Japanese Fighting Dog at times.

The Tosas never demonstrate any aggression towards humans usually as they are affectionate, loyal, and gentle.

They can however be very aggressive to other dogs and are not usually considered a good pet dog for families with other dogs. They are also not a good choice for families with small children.