Ishii Iron Works Co., Ltd. engages in the design, development, and manufacture of spherical tanks and low-temperature storage tanks. It operates through the Steel Structure and Real Estate segments. The Steel Structure segment provides design, construction, installation, and engineering services for oil and storage tanks, steel frames, chemical industry equipment, and pool steel structures. The Real Estate segment deals with real estate leasing business. The company was founded by Takichi Ishii in March 1900 and is headquartered in Tokyo, Japan.