ShieldAzure semée-de-lys Or, two bars Gules fimbriated of the second (Or) and overall a chevron rompu Argent.
CrestThat for the regiments and separate battalions of the Army Reserve: On a wreath of the colors Or and Azure the Lexington Minute Man Proper. The statue of the Minute Man, Captain John Parker (H.H. Kitson, sculptor), stands on the Common in Lexington, Massachusetts.
ShieldThe field, azure and semée-de-lys, is taken from the coat of arms of the Province of Artois (Pas de Calais) where the Regiment received its baptism of fire and where, when in the front line, a detachment repulsed a German raiding party of greatly superior numbers, the two survivors of the attack receiving the British Military Cross for exceptional heroism in battle. The chevron rompu represents the Regiment in the Meuse-Argonne offensive September 26-30, 1918, October 4, 1918, and especially November 1-2, 1918, when, as part of the 80th Division, it broke the German lines (Sector St. George's - St. Juvin, Department of Ardennes) enabling the Division to advance 24 kilometers in six days and capture the town of Buzancy, the key-point of the German position. The two bars gules are taken from the Washington coat of arms to indicate the home station of the Regiment. The motto, Forward, is suggested by the history of the Regiment in the Meuse-Argonne offensive and the use of the word in connection with the commendatory letters and telegrams published in G.O. No. 19, Hq. 80th Division, November 11, 1918.
CrestThe crest is that of the United States Army Reserve.
The coat of arms was originally approved for the 320th Infantry Regiment on 24 January 1925. It was redesignated for the 320th Infantry Regiment and amended to remove the Organized Reserves crest on 25 August 1943. The insignia was redesignated for the 320th Regiment and amended to restore the Army Reserve crest on 3 December 1959.