Shield
Per fess dancett of four Argent and Gules in base a bayonet fesswise of the first, a chief tierced per fess of the like, the second and Azure.
Crest
On a wreath of the colors Argent and Gules, a delta formed by a wavy band Azure bearing a narrow band of the first above the horns of a water buffalo Proper, and issuant from within the inner horizontal base and surmounting the upper area three stylized stalks of rice Or.
Motto
FIRST IN - LAST OUT.
Shield
Red and white are the colors for the Corps of Engineers. The four red points represent the battle honors awarded the unit for service during World War II; they also represent the teeth of a saw, an item of Engineer equipment, which is used with the bayonet to indicate the engineering-combat function of the Battalion. The three stripes at the top simulate the stripes in the Flag of the Territory of Hawaii, where the organization was activated. They also allude to the Meritorious Unit, Philippine Presidential and Korean Republic Presidential citations awarded the Battalion; the blue stripe symbolizes service in Korea.
Crest
Service in the Philippines, WWII and in the Korean War is referred to by the horns of the water buffalo, which is indigenous to those areas. The rice stalks allude to service in Vietnam, the three stalks referring to the three decorations: the Meritorious Unit Commendation, Vietnamese Cross of Gallantry with Palm and the Vietnamese Civil Actions Medal awarded the Battalion. The blue water symbol alludes to the waters of the Pacific, the Battalion's home area.
The coat of arms was approved on 18 October 1954. It was amended to add a crest on 24 September 1973.