Keiichiro Hamaguchi (born 1958) is a Japanese researcher specializing in labor policy and labor law. Born in Osaka Prefecture, he graduated from the Faculty of Law at the University of Tokyo and joined Japan's Ministry of Labour in 1983, working in areas including labor relations, labor standards, and employment policy. He later served at Japan's Mission to the European Union and held academic positions at the University of Tokyo and the National Graduate Institute for Policy Studies. He is currently Director General of the Research Institute for Labour Policy at the Japan Institute for Labour Policy and Training. His research examines Japan's employment system, labor relations, non-regular employment, and employment issues affecting young people and women. In "Jobugata Koyo Shakai to wa Nani ka: Seishain Taisei no Mujun to Tenki," he contrasts job-based employment with Japan's membership-based employment system to explain the institutional roots of issues involving regular and non-regular workers, wages, dismissal, and the employment of women and older workers.