There are two types of PFI prisons. The first is a prison which entrusts the design, the building, and full maintenance and administration with private sectors such as Anglo-American private prisons. Another is a prison which is designed and built in the center by a private sector. They administer them with proprietary privileges of the center, and then, they hand them over to the government after completing a certain business period like the continental private prisons. Japanese PFI prisons are the latter with co-administration of public officials and private sectors The writer believes that there are mainly three circumstances such as the countermeasure to the prison overcrowding, regulatory reform, and penal reform, being the reason for the PFI prisons being introduced into our country. And the writer considers that the development of Japanese PFI prisons is divided into five stages. The first stage is the PFI prisons which entrusts the design, the building, and a part of the maintenance and the administration with private sectors such as Mine Rehabilitation Program Center and Shimane-Asahi Rehabilitation Program Center.The second stage is the PFI prisons in which non-compulsory services is entrusted to these institutions that the government designed and built such as Kitsuregawa Rehabilitation Program Center and Harima Rehabilitation Program Center.The third stage is the existence of prisons such as the Kurobane Prison, Shizuoka Prison, and Kasamatsu Female Prison adopt a way to entrust a part of administration. The fourth stage is the PFI prisons adopting methods to entrust a part of general affairs in the Fuchu Prison and Tachikawa Detention Center, and methods to entrust a partial food supply like the Osaka Detention Center, Iwakuni Female Prison, and Kochi Prison. The privatization of catering is the characteristic of this stage.The fifth stage is the International Synthetic Center of judicial Affairs which is expected to complete in 2017. The government authority will entrust part of the administration and maintenance to private sectors utilizing the PFI method. The government expects that administrative efficiency, accommodation related to prison services with the high quality, and substantiality of correction medical treatment will be achieved.The thoroughness of allotment between the State and private sector is a key to the task of prison PFI business. And it is necessary to preserve the fairness and objectivity of transacting services, and to preserve the supervision and/or the effective monitoring system of the government.