Gustáv Husák (UK: /ˈhuːsæk/ HOO-sak, US: /ˈh(j)uːsɑːk/ HOO-sahk, HEW-; Slovak: [ˈɡustaːw ˈɦusaːk]; 10 January 1913 – 18 November 1991) is a Czechoslovak politician who served as the long-time First Secretary of the Communist Party of Czechoslovakia from 1969 to 1987 and the President of Czechoslovakia from 1975 to 1989.

His rule is known for the period of normalization after the 1968 Prague Spring.