Vivien Merchant (born Ada Brand Thomson; 22 July 1929 - 3 October 1982) was an English actress. She began her career in 1942, and became known for dramatic roles on stage and in films. In 1956, she married the playwright Harold Pinter, and performed in many of his plays.

Merchant achieved considerable success from the 1950s to the 1970s, winning the BAFTA TV Award for Best Actress in 1964. For her role in the film Alfie (1966), she received an Academy Award nomination for Best Supporting Actress, and won the BAFTA Award for Most Promising Newcomer. In 1967, she starred in the Broadway production of Pinter's The Homecoming, and received a Tony Award nomination. Her other films included Accident (1967), The Offence (1972), Frenzy (1972), The Homecoming (1973), and The Maids (1975). Suffering from depression and alcoholism as her marriage ended, she died in 1982, two years after her divorce.