The 1st Parliament of Singapore was a meeting of the Parliament of Singapore. It commenced its first and only session on 8 December 1965 and was dissolved on 8 February 1968. The session was boycotted by the Barisan Sosialis (BS), refusing to take up their seats in Parliament.
The members of the 1st Parliament had been elected in the 1963 general election to the 3rd Legislative Assembly of Singapore, which was renamed as the Parliament of Singapore following Singapore's independence in 1965. Parliament was controlled by a People's Action Party (PAP) supermajority, led by Prime Minister Lee Kuan Yew and his Cabinet. The Speakers were A. P. Rajah and then Punch Coomaraswamy.
The Parliament had 12 changes throughout the term, the most for any Parliament to date as of ; 11 members from Barisan Sosialis (BS), alongside Fong Kim Heng as the only PAP's MP, were vacated and precipitated a series of elections between 1966 and 1968.