Jack Kent (1870 in Lambeth, London – 1946) was a British politician and an important figure in the early history of the Socialist Party of Great Britain. Kent was a well-known member of the Social Democratic Federation, being a writer for Justice from 1897 and a speaker and lecture secretary. In 1902 he was on the SDF Executive Committee and was delegate for West Ham Central during the 1902 SDF Conference. He was not originally an impossibilist but came over after the 24 April meeting, revealing the manoeuvrings of Hyndman clique.