Secretary of State for Defence

The secretary of state for defence, also known as the defence secretary, is a secretary of state in the Government of the United Kingdom, with responsibility for the Ministry of Defence. As a senior minister, the incumbent is a member of the Cabinet of the United Kingdom.

The post of secretary of state for defence was created on 1 April 1964, replacing the positions of minister of defence, first lord of the admiralty, secretary of state for war, and secretary of state for air, while the individual offices of the British Armed Forces were abolished and their functions transferred to the Ministry of Defence. In 2019, Penny Mordaunt became the UK's first female defence secretary.

The secretary of state is supported by the other ministers in the defence ministerial team and the MOD permanent secretary. The corresponding shadow minister is the shadow secretary of state for defence, and the secretary of state is also scrutinised by the Defence Select Committee.

The current secretary of state for defence is Wes Streeting. He was appointed on 20 July 2026 following Keir Starmers' resignation.