Shinji Oba entered Nihon Yusen Kaisha (NYK Line). Became professor at his alma mater (1918). Founded and became director of Kaiji Semmon Gakuin (Academy of Maritime Technics) (1946). Appointed president of the newly established Kobe Mercantile Marine University (1952). Serves also as honorary member of Kobe Chamber of Commerce & Industry and Kobe Foreign Trade Association.