Leon Brittan, Baron Brittan of Spennithorne, PC (born September 25, 1939), is a barrister, a British politician, and a former Conservative Member of Parliament and former member of the European Commission.

Educated at Trinity College, Cambridge where he was President of the Cambridge Union Society, he started his career as a lawyer. After unsuccessfully contesting the constituency of North Kensington in 1966 and 1970, he was elected to parliament in the general election of February 1974, and became an opposition spokesman in 1976. He was made a Queen's Counsel in 1978. Between 1979 and 1981 he was Minister of State at the Home Office, and then was made Chief Secretary to the Treasury, a Cabinet position. At the 1983 election his seat changed to Richmond. He was Secretary of State for the Home Department from 1983 to 1985, and was then moved to Secretary of State for Trade and Industry. He resigned over the Westland affair.

He was made a commissioner at the European Commission in 1989, resigning as MP at this time, and became vice-president, but resigned with the rest of the commission in 1999 amid accusations of widespread fraud.

During 14 years as an MP, he served the constituencies of Cleveland and Whitby (1974-1983) and Richmond (1983-1988).

He was created Baron Brittan of Spennithorne in 1999 and is an advisory director to Unilever.