This article is about the poltical party that existed from 1931-1945. For the party that existed in the late 1950s see National Labour Party (UK 1950s). The National Labour Party was also the name of an Irish political party (a split from the Irish Labour Party) active in the 1940s and 1950s.

The National Labour Party was a group founded around the British Prime Minister Ramsay Macdonald after he was expelled from the Labour Party in 1931. It contested the 1931 election and the 1935 election, and was viewed by the mainstream Labour party as 'traitors'.

Just before the 1945 election it formally dissolved itself and its remaining MPs either retired from Parliament, stood as "National" supporters of the continuation of the National Government (better known as Churchill's "Caretaker Government") or stood as independents.