Kate Aitken (1891-1971) was a Canadian radio and television broadcaster in the 1930s, 1940s and 1950s. As Mrs. A, she was one of the most famous hosts on the Canadian Broadcasting Corporation in her era.

Aitken, born Kate Scott in Beeton, Ontario, worked as an entrepreneur, teacher and journalist both before and after marrying local businessman Henry Aitken. As a journalist, she once interviewed Benito Mussolini.

She subsequently taught cooking, including at the Canadian National Exhibition. She was offered a radio show in 1934, when a broadcaster at CFRB broke her leg and the station manager needed an emergency replacement. The show was syndicated to other radio stations, and was eventually picked up by the Canadian Broadcasting Corporation.

Aitken primarily covered homemaking subjects such as cooking and etiquette, but also did some documentary journalism, including a profile of Hungarian refugees in 1956. Aitken also became an early host on CBC television, and wrote newspaper columns and books.

She retired in 1958, but continued to work for UNICEF, and served on the CBC's board of directors. She died in Beeton in 1971, on the same farm where she had lived most of her life.