Margaret Lockwood, CBE (15 September 1916 - 15 July 1990) was a British actress.

Christened Mary Margaret Lockwood Day in Karachi, British India (now Pakistan), Lockwood's family returned to the United Kingdom while she was a child.

She made her stage debut at the age of 12, and trained at the Royal Academy of Dramatic Art in London, where she was seen by a talent scout and signed to a contract. In 1935 she appeared in the film version of Lorna Doone. Her most successful film of the 1930s was Alfred Hitchcock's The Lady Vanishes.

In the early 1940s she changed her on-screen image to play villainesses in both contemporary and period films, becoming the most successful actress in British films during that period. Her greatest success was in the title role in The Wicked Lady (1945), a film which was controversial in its day and brought Lockwood considerable publicity.

She continued to act until the late 1970s, and was created a CBE in 1980. Her acceptance of this award marked her last public appearance.

She lived her final years in seclusion and died in Kensington, London, UK, from cirrhosis of the liver, aged 73.

She is survived by her daughter, actress Julia Clark (neé Margaret Julia de Leon).