The Institute houses documents and materials related to contemporary law.
The Institute also collects, organizes, and stores valuable research materials in individual fields.
Currently, the following collections are housed at the Institute.
- Nagai Bunko (Education Law Corner)
- Morinaga Bunko (donated by the late lawyer Eizaburo Morinaga)
- Morikawa Collection (Gift of Attorney Kinju Morikawa)
- Kurita Bunko (construction contract-related materials, etc.)
- Umabukuro Documents (case files, cash books, journals, etc. of a lawyer in the Meiji era)
- Nishida Bunko
- Sodei Bunko (materials and documents related to the Allied occupation of Japan)
- Ota Bunko (Gift of the late Ota Katsuhong, related to contemporary Chinese politics and diplomacy)