ShieldAzure, on a bend Or three alerions Gules.
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.
MottoFIDEM PRAESTABIMUS (We Will Keep the Faith).
ShieldThe shield is blue for Infantry. The yellow or gold bend charged with the three alerions is taken from the arms of Lorraine, the tinctures being reversed, and the three alerions allude to the three engagements - Lorraine, St. Mihiel, and Meuse-Argonne - in which the organization took part during World War I.
CrestThe crest is that of the United States Army Reserve.
The coat of arms was originally approved for the 355th Infantry Regiment on 2 May 1927. It was redesignated for the 355th Regiment on 26 January 1962.