三井不動産 (Mitsui Fudosan) is a leading real estate development company in Japan, established in 1941. It is part of the larger Mitsui Group, a prominent conglomerate. The company focuses on various sectors, including residential, commercial, and mixed-use properties, and is known for its innovative urban development projects. In addition to real estate development, 三井不動産 also engages in property management and investment. The company has expanded its operations internationally, with projects in countries like the United States and China, contributing to its reputation as a global player in the real estate market.