John Wills Greenslade (January 11, 1880 – January 6, 1950) was a highly decorated officer in the United States Navy with the rank of Vice Admiral. He enjoyed a significant military career, participating in several conflicts and distinguished himself during World War I as Commanding officer, USS Housatonic and during World War II as Commander, Western Sea Frontier and Commandant, Twelfth Naval district with headquarters at Mare Island Naval Shipyard.