Rideau Centre is a three level shopping center on Rideau Street in downtown Ottawa, Ontario. It borders on the Byward Market, the Rideau Canal, the Mackenzie King Bridge, and Nicholas Street.

At the time of its construction in 1981-82 the Rideau Centre was somewhat controversial. Many people were opposed to the destruction of several heritage buildings on Rideau Street. Others feared the impact of increased traffic and buses on the area.

Today the Rideau Centre is a major transportation and shopping hub in downtown Ottawa. It is the most popular and the largest mall in the city. Prominent tenants include Shoppers Drug Mart, and Sears. The Bay and Chapters are located adjacent to the Rideau Centre, with an enclosed walkway to the Bay located on the second floor.

The Rideau Centre incorporates the Westin Hotel, a movie theatre, a convention centre, two (originally three) large department stores, and about 230 other shops. The retail development is estimated to be about 1,500,000 square feet, making it the largest shopping area in Ottawa. The convention centre is currently quite small, but it is planned for enormous expansion, which will increase its size by a factor of between 3 and 6.