USCGC Thetis (WMEC-910) is a United States Coast Guard Famous-class medium endurance cutter. She is the 10th ship of the Famous Class cutters designed and built for the U.S. Coast Guard and the third Coast Guard cutter to bear the name. Laid down August 24, 1984 by Robert Derecktor Shipyard Incorporated of Middletown, Rhode Island. She was launched April 29, 1986 and named for the cutters USRC Thetis, which served from 1899 to 1916, and USCGC Thetis (WPC-115), which served from 1931 to 1947. The Greek goddess Thetis, incidentally, was the mother of Achilles. The Famous Class cutter Thetis was commissioned on June 30, 1989. She conducts patrols throughout the Caribbean and the Gulf of Mexico.

The Medium Endurance Cutter or WMEC is a type of United States Coast Guard Cutter mainly consisting of the 270-foot (82 m) Famous- and 210-foot (64 m) Reliance-class cutters. These larger cutters are under control of Area Commands. These cutters have adequate accommodations for crew to live on board and can do 6 to 8 week patrols.