There is a constructional difference in opportunities of learning medical oncology between cancer centers and university hospitals in Japan. The university is the only institution to provide oncology education for all medical students including those who will make a specialty of fields other than oncology. Since palliative and terminal care as well as primary and secondary cancer prevention have become more important recently, students who wish to become a primary physician need to learn medical oncology. The university plays a role in education for doctors in early postgraduate training. Whether they will have an interest in medical oncology depends entirely on the results of the education. The education for doctors in late postgraduate training is conducted at both cancer centers and university hospitals. The cancer centers have an enriched on-the-job training program (resident program), while such program has not been established in many university hospitals. This is partly because assignment of roles between a newly organized medical oncology department and traditional organ-specified departments remains in a chaotic state. Knowledge and insight on cancer biology have been even more essential for medical oncologists than before, but no chance to learn basic medical science is given to doctors in training, except for postgraduate students in universities and senior residents in cancer centers. There is a lot of argument about the identity of medical oncology in Japan. It should not be defined in a hurry, but it is being gradually established as medical oncologists will grow up to be the support and driving force of future medical oncology in Japan.