Winzer joined the Socialist Unity Party, the East German communist party, in 1946, and he became a member of its central committee in 1946.[3] He was named the deputy editor of the party's official paper Neues Deutschland in 1949.[4] Winzer was Secretary of State from 1949 to 1956 and First Deputy Minister of Foreign Affairs from 1956 to 1965.[3] He served as Minister of Foreign Affairs from 1965 to 1975. He was removed from his post due to ill health[5] and died at age 72 on 3 March 1975.[6]