The first USS Guinevere (SP-512) was a United States Navy patrol vessel in commission from 1917 to 1918. Guinevere was built in 1908 as a private steam and sail yacht of the same name by George Lawley & Son at Neponset, Massachusetts. On 10 June 1917, the U.S. Navy acquired her from her owner, Edgar Palmer of New York City, for use as a section patrol vessel during World War I. She was commissioned as USS Guinevere (SP-512) on 20 July 1917.