Sydney Woodhull was a Singaporean politician, political prisoner. He was a founding member of the University Socialist Club and the People's Action Party.
Sydney Woodhull entered the University of Malaya in 1951 as a Sultan Librahim scholars from Johor. He was a founding member of the Socialist Club in 1953, serving as Financial Secretary in the first Central Working Committee. He was also involved in the Fajar controversy because of his contribution to the Fajar magazine and occasional attendance at group's meetings although he was not the member of the Fajar editorial board.
When the PAP split in 1961, he joined the Barisan Sosialis. He was arrested and detained without trial under Operation Coldstore in 1963 and exiled to Kuala Lumpur. He was released in November that year and went to the United Kingdom. He retired in 2001 as a lawyer.