The 40th New Zealand Parliament was a term of the Parliament of New Zealand. Its composition was determined by the 1981 election, and it sat until the 1984 election.

The 1981 New Zealand general election, held on 28 November 1981, was a nationwide vote to determine the shape of the 40th New Zealand Parliament. It saw the governing National Party, led by Robert Muldoon, win a third term in office, but the opposition Labour Party, led by Bill Rowling, won the largest share of the votes cast. Social Credit also won over 20% of the vote – their best result ever – but received no new seats.