The Union Building is a building on The Bund in Shanghai, China. It is located at No. 3, the Bund (formerly no. 4). Completed in 1916, the building was used by a number of insurance companies. The six-storey building was the first work in Shanghai of P&T Architects and Surveyors (Palmer & Turner), and was the first building in Shanghai to use a steel structure. The building occupied 2241 square metres, with a floor area of 13760 square metres. Because it had a narrow frontage onto the Bund, the main door was located on the adjacent Guangdong Road.
The building is in Neo-Renaissance style with a symmetrical facade, but with some Baroque style details. The roof features a domed corner pavilion. The Union Bank then purchased the building. In 1949 the Union Bank evacuated from Shanghai in the wake of the Communist takeover. From 1953 the building was used by the Shanghai Civil Architecture and Design Institute. In 1997 a private equity fund from Singapore purchased the building, and in 2004 converted it to a shopping centre, called "Three on the Bund".