How to Use for Genealogy Research
The Ministry of Justice (MOJ) oversees Japan’s koseki (family register) system. The koseki has been recorded continuously since the Jinshin Koseki of 1872, and the oldest surviving records can reach back to the late Edo period.
Overview
The MOJ Civil Affairs Bureau administers the system; municipal offices nationwide handle day-to-day operations. Koseki are official documents recording births, marriages, deaths, divorces, and changes of nationality.
Key Documents for Genealogy
- Koseki Tōhon: Full copy of the current register
- Jokoseki Tōhon: Removed register—records from after all members left through death, marriage, or address change
- Kaiseigenkoseki Tōhon (harako): Pre-revision registers from Meiji, Taisho, and Showa eras
- Koseki no Fuhyō: Address history linked to the register
Retention period is 150 years (formerly 80 years). Destroyed records cannot be retrieved.
