Windsor House, Commercial complex in Causeway Bay, Hong Kong.

Windsor House is a 38-story commercial tower on Gloucester Road that combines retail shops and restaurants on the lower levels with office spaces above. The building sits within a dense cluster of high-rises that define this busy neighborhood's skyline.

The tower was built in 1979 on the site of a former Dairy Farm cold storage facility, marking the area's transition from industrial to commercial use. This change reflected Hong Kong's broader shift toward service and office-based industries.

The building is also known as the AIA Tower, and its podium houses the Windsor House shopping mall. The Chinese name was fixed as 皇室大廈 in early 1980, while the English name stayed Windsor House. Tenants have included Chinese Estates and AIA on the 22nd and 33rd floors.

The tower connects directly to Exit E of Causeway Bay MTR station and is within short walking distance of the Paterson Street tram stop. Both transit options make it easy to reach from different parts of the neighborhood.

In October 1983 the lobby's marble walls were said to show a fox-spirit pattern, drawing crowds for several days until the owner replaced the marble. The tale was linked to a rumour about a baby who died after a full-moon banquet at the Maxim Palace restaurant in the mall.