Objectives: The aim of this study was to study the necessary competencies for specialist occupational physicians in Japan and the effective training methods for acquiring them. Methods: A competency list (61 items) was developed for the questionnaires in the study by making use of existing competency lists from the Japan Society for Occupational Health (JSOH) as well as lists from the US and Europe. Certified senior occupational physicians (CSOPs) in the certification program of the JSOH completed a questionnaire on the necessary competencies. Examiners of the examination for certified occupational physicians (COPs) completed another questionnaire on effective training methods. Results: All 61 competencies in the questionnaires were evaluated as “necessary”. Some of the competencies in the list from the JSOH were evaluated lower than the items added from the American and European lists. When the respondents were categorized into a “practical group”, the members of which mainly provided occupational health services, an “academic group”, the members of which belonged to research or education institutes such as medical schools, and all others, the practical group evaluated some competencies significantly higher than the academic group, particularly those related to work accommodation. Among three options for training methods, the most effective methods were lectures and textbooks for 5 competency items, on-the-job training (OJT) for 30 items, and case-based learning (CBL) for 29 items. Conclusions: Some competencies should be added to the JSOH list. CBL should be introduced in training programs for specialist occupational physicians.(J Occup Health 2015; 57: 126—141)