Don Benjamin Rupasinghe Gunawardena (12 March 1904 - 26 December 1971: Sinhala: රොබට් ගුණවර්ධන), popularly as Robert Gunawardena, was a Sri Lankan Marxist politician and diplomat. He was one of the founders of the Lanka Sama Samaja Party, which was the first political party in Sri Lanka, and served as the long time MP for Kotte. He was the leader of the Suriya-Mal Movement and served as ambassador to China between 1965 and 1970.