 He was re-elected twice (in 1965 and 1970) to the legislature for Horana from the Sri Lanka Freedom Party (SLFP).Wickremanayake received his first ministerial appointment in 1970, when he was appointed Deputy Minister for Justice in the United Front government under Prime Minister Sirimavo Bandaranaike.In 1975, Wickremanayake was appointed Minister of Plantation Industries and the next year was also Minister of Justice.