Lee was born in Kuala Lumpur and was educated at Victoria Institution. He was trained as a medical doctor, but spent most of his life as a political leader. Lee served in Singapore's Legislative Assembly as a representative of the PAP following the 1959 election. In 1960 he served as the Parliamentary Secretary for Home Affairs. In 1961, Lee and 13 other members of the assembly broke away from the PAP and formed the Socialist Front. Lee led the party in the 1963 elections, in which they won 13 of the 51 seats. Lee was noted for his pro-leftist stance and oratory skills. In 1961, he made the longest speech in the history of Singapore's Legislative Assembly which lasted seven hours on the subject of Singapore's proposed merger with Malaya. The Socialist Front was Singapore's main opposition party at the time of the country's independence in 1965. But the party boycotted the first post-independence general election in 1968, allowing the PAP to win all 51 of the seats in Parliament. The Socialist Front never managed to regain a significant role in Singapore's political scene after this, and in 1988, the party merged with the Workers' Party. At the 1988 general election, Lee stood as a Workers' Party candidate in the Eunos Group Representation Constituency along with fellow party members Francis Seow and Mohd Khalit bin Mohd Baboo. They lost very narrowly to the PAP's team in the constituency by 49.1% of the votes to 50.9%. Only one opposition MP was returned to Parliament at that election. As the Workers' Party's team in Eunos had garnered a higher percentage of the vote than any other opposition losing candidates, the party was eligible to nominate two members of its team from Eunos to become Non-constituency MPs. The party had refused to nominate NCMPs in the past, but this time they nominated Lee and Seow to become NCMPs. Seow was subsequently accused of espionage and fled to the United States before he could take up his NCMP seat. But Lee became Singapore's first-ever NCMP, serving until the 1991 general election. In Parliament, he raised several issues, including the Internal Security Act, living costs and welfare. Lee again stood in Eunos GRC at the 1991 general election. He and fellow party members Jufrie Mahmood, Neo Choon Aik and Wee Han Kim again lost narrowly to the PAP's team by 47.6% of the votes to 52.4%. However no NCMP seats were offered following that election as the opposition parties won a combined total of four elected seats. His eldest son Lee Yew Kwong died in 1992. Lee left the Workers' Party in 1996, citing differences with the party's leader, Joshua Benjamin Jeyaretnam. Lee died of lung cancer on 18 July 2002. He leaves behind his wife Kathleen Fam Yin Oi, two sons, Peter LeeYew Chung and David Lee Yew Keong, and a daughter, Lee Yu Lian.
