The United Nations Interim Force in Lebanon, or UNIFIL, was created by the United Nations, with the adoption of Security Council Resolution 425 and 426 on 19 March 1978, to confirm Israeli withdrawal from Lebanon which Israel had invaded five days prior, restore international peace and security, and help the Government of Lebanon restore its effective authority in the area.

The first UNIFIL troops were deployed in the area on 23 March 1978; these troops were reassigned from other UN peacekeeping operations in the area (namely the United Nations Emergency Force and the United Nations Disengagement Observer Force Zone).

During the occupation, UNIFIL's function was mainly to provide humanitarian aid.

UNIFIL's mandate is renewed by United Nations Security Council annually. Current mandate expires on 31 August 2012.

UNIFIL is tasked with achieving the following objectives:

Mandating resolutions by the United Nations:

Prior to the 1982 Lebanon War, on 2 January 1982 two Ghanaian soldiers guarding a UNIFIL position were attacked by unidentified persons and one of the soldiers was shot and subsequently died. During the 1982 Lebanon War, UN positions were overrun, primarily by the SLA forces under Saad Haddad. This was the Lebanese paramilitary force supported by the IDF in Southern Lebanon. Beginning in 1985, Israel scaled back its permanent positions in Lebanon, although this process was punctuated by brief invasions and bombings, as in Operation Accountability in 1993 and Operation Grapes of Wrath in 1996. In 1999, Israel undertook a withdrawal, which concluded in 2000 and enabled UNIFIL to resume its military tasks.^{[clarification needed]}