South West Pacific Area (SWPA) was the name given to the Allied supreme military command in the South West Pacific Theatre of World War II. It was one of four major Allied commands in the Pacific theatres of World War II, during 1942–1945. SWPA included the Philippines, Borneo, the Dutch East Indies (excluding Sumatra), Australia, the Territory of New Guinea (including the Bismarck Archipelago), the western part of the Solomon Islands and some neighbouring territories. The supreme commander, General Douglas MacArthur, was in charge of primarily United States and Australian forces. Dutch, Filipino, British and other Allied forces also served in the SWPA.

The command was disestablished on 2 September 1945.

The name "South West Pacific Area" appears to have originated in British military circles in 1941, purely in reference to British forces under the short-lived American-British-Dutch-Australian Command (ABDA). The rapid Japanese advance through the Dutch East Indies effectively divided the "ABDA Area" in two, and in late February 1942, ABDA was wound up at the recommendation of its commander, the British General Archibald Wavell, who—as Commander in Chief in India—retained responsibility for Allied operations in Burma and Sumatra (which fell to the Japanese on 28 March 1942), and against Japanese held Singapore, Malaya and Thailand.

The South West Pacific Theatre, technically the South West Pacific Area, between 1942 and 1945, was one of two designated area commands and war theatres enumerated by the Combined Chiefs of Staff (CCoS) of World War II in the Pacific region.

The South West Pacific theatre included the Philippines, the Dutch East Indies (excluding Sumatra), Borneo, Australia, the Australian Territory of New Guinea (including the Bismarck Archipelago), the western part of the Solomon Islands and some neighbouring territories. The theatre takes its name from the major title of the Allied command, which was known simply as the "South West Pacific Area", with the commanding officer: "Commander South West Pacific Area", the first being General Douglas MacArthur–appointed in March 1942.

On March 30, 1942, the Allied South West Pacific Area command (SWPA) was formed and U.S. General Douglas MacArthur was appointed Supreme Allied Commander South West Pacific Area. The other theatre, known as the Pacific Ocean theater of World War II, was commanded by Admiral Chester Nimitz.