Naval Mobile Construction Battalion 25 or NMCB 25 is a Navy Reserve Seabee unit that is headquartered at Port Hueneme, CA.

Its World War II predecessor was one of three CBs transferred to the Marine Corps in the late summer of 1942 as combat engineers.

On 13 September 1942, the 25th Naval Construction Battalion was commissioned at Camp Bradford, Virginia and sent to Ports Hueneme.

Headquarters and A, C & D Companies were transferred to the Marine Corps and sent to Camp Elliot, San Diego on 31 October.

[1] Camp Elliot was the home of the Fleet Marine Force (FMF) Training Center, West Coast.

However, the battalion was then attached to III Amphibious Corps, FMF for administrative purposes and to the 3rd Marine Division operationally.

Dozers were needed so badly that those organic to the artillery units had to be reassigned until they were not required.

Afterwards the Marines assessment was that: "in all future amphibious operations a Seabee component or one with equal road building capabilities be assigned to the assault".

On 17 August, the battalion returned to the Navy administration and assigned to the 27th NCR of the 5th Construction Brigade.

[11] Note: 25 NCB was the only unit to serve with Army, Navy and Marine Corps formations during WWII.

[13] note: On Bougainville the 3rd Combat Team was awarded a Naval Unit Commendation.

[22] The World War II unit logo borrowed the shield "style or pattern" used for the Third Marine Division's crest.

The unit number 25 is emblazoned in the center with the letters "C B" and there are crossed anchors behind shield.