As a young child, Goonewardene was educated at St. John's College, Panadura and S. Thomas' College, Mount Lavinia; S. Thomas' is considered to be the most prestigious school in Ceylon, with notable alumni including four former prime ministers of Sri Lanka.; ; Goonewardene's father, Andrew Simon Goonewardene, later sent him to a public (in the British sense of the term) boarding school, Rydal School, in north Wales with the aim of making him a Methodist priest. Instead, Goonewardene became influenced by the widespread Marxist teachings of the time, notably conflicting with his own privilege. This was a major factor leading him to pursue a BSc degree in economics from the London School of Economics, where he was shaped by the teachings of his professor, Harold Laski. He was admitted to the bar at Gray's Inn, one of the four Inns of Court in London, in 1933 but never practised law.; ; ;
