On a yellow disk 3 1/4 inches in diameter with a 1/8 inch edge, a conventionalized black volcano emitting smoke, the volcano charged with three yellow mullets in fess.
The volcano represents the area in which the units were located. The three stars are taken from the Philippines Coat of Arms which represents the principle islands - Luzon and Mindanao, and the Visayan Islands.
The insignia was requested for the lst Philippine Battalion; however the unit was changed to the lst Philippine Regiment. The authorization approved on August 6, 1942, was for all Philippine Battalions.