1, Japanese doctors usually have 2 to 5 years. The longest is five years. It mainly depends on your personal efforts and the success rate of your thesis. Japanese doctors are called postdoctoral courses, which usually last for three years. The doctor of medicine is longer.

2. The doctoral program in Japan is a five-year program, which is divided into two years in the early stage and three years in the later stage. Japan's doctoral preparatory course is equivalent to a master's degree, which takes 2 years. In the postdoctoral stage, doctors need to study for three years and complete doctoral courses in Japanese universities. They have high research ability and profound basic knowledge necessary for a scientist to independently carry out research activities in the professional field.

3. There are 19 doctoral degrees awarded by the graduate school of Japanese universities: academic, literature, education, theology, sociology, law, political science, economics, business, management, science, medicine, dentistry, pharmacy, health care, engineering, agronomy, veterinary medicine and aquaculture.