The penal system of Japan is part of the criminal justice system of Japan. It is intended to resocialize, reform, rehabilitate and punish offenders. The penal system is operated by the Correction Bureau of the Ministry of Justice.

Within the criminal justice system of Japan, there exist three basic features that characterize its operations. First, the institutions—police, government prosecutors' offices, courts, and correctional organs—maintain close and cooperative relations with each other, consulting frequently on how best to accomplish the shared goals of limiting and controlling crime. Second, citizens are encouraged to assist in maintaining public order, and they participate extensively in crime prevention campaigns, apprehension of suspects, and offender rehabilitation programs. Finally, officials who administer criminal justice are allowed considerable discretion in dealing with offenders.