The Papuan Infantry Battalion (PIB) was an infantry battalion of the Australian Army that was raised for service during World War II. Formed in early 1940, the battalion was recruited from the territory of Papua and was intended to be used to defend the territory in the event of a Japanese invasion. Commanded by European officers and non-commissioned officers, following the outbreak of the Pacific War, the PIB served in a number of campaigns against the Japanese until the end of the war. Together with several New Guinea infantry battalions, the PIB was formed into the Pacific Islands Regiment in late 1944. It was disbanded in mid-1946.