Defence Intelligence (DI) is an organisation within the United Kingdom intelligence community which focuses on gathering and analysing military intelligence. It differs from the UK's intelligence agencies in that it is an integral part of a government department – the Ministry of Defence (MoD) – rather than a stand-alone organisation. The organisation employs a mixture of civilian and military staff and is funded within the UK's defence budget. The organisation was formerly known as the Defence Intelligence Staff (DIS), but changed its name in 2009.

The Government of the United Kingdom maintains several intelligence agencies that deal with secret intelligence. These agencies are responsible for collecting, analysing and exploiting foreign and domestic intelligence, providing military intelligence, and performing espionage and counter-espionage. Their intelligence assessments contribute to the conduct of the foreign relations of the United Kingdom, maintaining the national security of the United Kingdom, military planning, public safety, and law enforcement in the United Kingdom. The four main agencies are the Secret Intelligence Service, the Security Service (MI5), the Government Communications Headquarters (GCHQ) and Defence Intelligence (DI). The agencies are organised under three government departments, the Foreign Office, the Home Office and the Ministry of Defence.