USS Katherine K. (SP-220) was a United States Navy patrol vessel and tug in commission from 1917 to 1919.

Katherine K. was built as a civilian tug of the same name in 1894 by M. D. Battomer at Baltimore, Maryland.

The U.S. Navy acquired Katherine K. from her owner, Samuel H. Freas of Miami, Florida on 9 June 1917 for World War I service as a tug and patrol vessel.

She was enrolled in the Naval Coast Defense Reserve on 16 June 1917, delivered to the Navy at Key West, Florida, on 10 July 1917, and commissioned as USS Katherine K. (SP-220) on 7 September 1917.

Assigned as a section patrol ship to the 7th Naval District, Katherine K. patrolled the waters in and around Key West and served as a harbor tug and target-towing tug during World War I.