The 1959 United Kingdom general election was held on Thursday, 8 October 1959. It marked a third consecutive victory for the ruling Conservative Party, now led by Prime Minister Harold Macmillan. For the second time in a row, the Conservatives increased their overall majority in Parliament, this time to a landslide majority of 100 seats, having gained 20 seats for a return of 365. The Labour Party, led by Hugh Gaitskell, lost 19 seats and returned 258. The Liberal Party, led by Jo Grimond, again returned only six MPs to the House of Commons, but managed to increase its overall share of the vote to 5.9%, compared to just 2.7% four years earlier.

The Conservative and Unionist Party, commonly the Conservative Party and colloquially known as the Tories, is one of the two main political parties in the United Kingdom, along with the Labour Party. It is the current governing party, having won the 2019 general election, and has been the primary governing party in the United Kingdom since 2010. The party sits on the right-wing to centre-right of the political spectrum. It encompasses various ideological factions including one-nation conservatives, Thatcherites, and traditionalist conservatives. The party holds the annual Conservative Party Conference, at which senior Conservative figures promote party policy.