USCGC Cactus (WLB-270) is a sea going buoy tender (WLB). A Cactus-class vessel, she was built by Marine Ironworks and Shipbuilding Corporation in Duluth, Minnesota. Cactus's preliminary design was completed by the United States Lighthouse Service and the final design was produced by Marine Iron and Shipbuilding Corporation in Duluth. On 31 March 1941 the keel was laid, she was launched on 25 November 1941 and commissioned on 1 September 1942. The original cost for the hull and machinery was $782,381.