Shield
Azure, a chevron rompu point debased Argent between in chief a plate charged with the monogrammed "OT" of the shoulder sleeve insignia of the 90th Division Proper and in base two mullets of the second.
Crest
That for the regiments and separate battalions of the Army Reserve: From a wreath Argent 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.
Motto
SIEMPRE ALERTA (Always on Alert).
Shield
The shield is blue, the Infantry color. The broken rompu point debased chevron indicates that the regiment pushed the German salient back at the Bois de Bantheville and Grand Carr Farm. The shoulder sleeve insignia indicates that the 357th Infantry was a unit of the 90th Division, the unit's former assignment. The two mullets (stars) represent the two major operations during World War I, as well as the dual source of the personnel.
Crest
The crest is that of the United States Army Reserve.
The coat of arms was originally approved for the 357th Infantry Regiment, Organized Reserves on 19 June 1925. It was amended to withdraw "Organized Reserves" from the designation and to delete the Organized Reserves' crest from the coat of arms on 16 June 1959. The insignia was amended to reinstate the crest of the Army Reserve on 7 August 1970. It was redesignated for the 357th Regiment on 8 July 1999.