Barnes Ratwatte (known as Barnes Ratwatte Dissawa ) (1883 – September 20, 1957) was a Ceylonese colonial-era legislator and a headmen. He was a member of the State Council and the Senate of Ceylon. He was appointed to the posts of Rate Mahatmaya and Dissawa of Sabaragamuwa by the British. He was the father of Sirimavo Bandaranaike, the first female Prime Minister in the world.
Born to Abeyratne Banda Ratwatte Basnayake and Thalgahagoda Lewke Punchi Kumarihamy, Barnes Ratwatte was educated at Trinity College, Kandy. One of his brothers was Sir Cuda Ratwatte Adigar former Mayor of Kandy and the other brother Harris Leuke Ratwatte who was former Diyawadana Nilame of Sri Dalada Maligawa, Kandy, He was a member of the State Council in 1936 to 1947 for Kegalle and United National Party Member of Parliament for Mawanella 1947 to 1952. 
He married Rosalind Mahawelatenne Kumarihamy, daughter of Mahawalatenne Rate Mahatmaya of Balangoda. They had six children including four sons Barnes Ratwatte II, Dr Seevali Ratwatte, Dr Mackie Ratwatte and Clifford Ratwatte, former Member of Parliament for Balangoda and Chairman of the State Plantations and Sri Lanka Tea Board. Of their two daughters; the eldest Sirimavo Ratwatte was married to Solomon West Ridgeway Dias Bandaranaike, son of Sir Solomon Dias Bandaranaike, the Maha Mudaliyar (chief native interpreter and advisor to the Governor), who became the third Prime Minister of Ceylon. The youngest daughter, Patsy Ratwatte was married to Colonel Edward James Divitotawela, who founded the Central Command of the Ceylon Army. His grand daughter Chandrika Kumaratunga was President of Sri Lanka and his grandson Anura Bandaranaike, was a former speaker and cabinet minister.