Mitsui Bunko is a research institution consisting of the main historical archive and the Mitsui Memorial Museum, which is housed in an annex. The historical archive was established in 1965 as a foundation and is engaged in the preservation of documentary materials on socioeconomic history dating back to the Edo Period (17th to 19th century), which it also makes available to the public and uses in investigation and research activities. The Mitsui Memorial Museum opened in October 2005 and engages in the preservation of artworks, which are also used for public exhibition and research purposes. The foundation's operations are financed by donations from members of the Mitsui Group. Mitsui has participated since the establishment of Mitsui Bunko, contributing thus to the preservation of traditional culture and the enhancement of academic research.

• Mitsui Bunko website