She was educated at the Princess of Wales' College, Colombo.In 1925 she married Reginald S.
Vincent Senanayke (1898-1946), a founding member of the Lanka Sama Samaja Party and its treasurer between 1935 and 1939.Senanayake was elected in 1947 at the 1st Ceylonese parliamentary elections, as the member for Kiriella, representing the Lanka Sama Samaja Party.
She polled 5,535 votes (35.5% of the total vote) winning against a field of four other male candidates, with her nearest opponent, T.
K.
W.
Chandrasekera, receiving 3,294 votes (21.1% of the total vote).
Senanayake failed to retain the seat at the 2nd parliamentary elections in 1952, where she received 3,192 votes (15% of the total votes), with the successful candidate, A.
E.
B.
Kiriella, polling 9,978 votes (48% of the total vote).