It was first activated as the 31st Air Base Gp about 5 Dec 1940 at Barksdale Fld and probably assigned to General Headquarters,AF (later AF Combat Command).

It had an Air Base Sq and Material Sq assigned. About 17 Jan 1941 Air Base Sq, 31st Air Base Gp was redesignated 32nd Air Base Sq and Materiel Sq, 31st Air Base Gp was redesignated 42nd Material Sq.

In April 1941, the Group moved to Davis-Monthan Fld where, in September 1941 it was reassigned to IV AF Base Command.

In January 1942 it moved to Sheppard Fld and in April, back to Davis Monthan Fld. About 13 Jun 42, in a general reorganization of base units, it was redesignated the 31st Service Group and lost the 32nd Air Base Squadron and its mission of running an air base. Instead, it was reorganized with two Service Squadrons (the 42nd was redesignated a Service Sq -- I do not have verified information on the second squadron, but the 56th, 305th, and/or 364th Service Squadrons may have been assigned).

It was reassigned to the IV Air Service Area Command as a Service Group and later to the Warner Robins Air Service Command. It made several moves, to Muroc AAF in November 1942, Biggs Fld in May 1943, Herbert Smart Airport later in 1943, Camp Campbell AAF around February 1944, and later to McCook AAF. At McCook it was reorganized as a new type Service Group, designed to support one, rather than two combat groups. Its service squadrons became an Engineering Sq and a Material Sq.

About Dec 44 all these units added an "Air" before their names, it was also reassigned to 20th AF at McCook.

In January 1945 it moved to North Fld, Guam, where it apparently remained until 24 August 1948. It was disbanded on 8 October 1948.