KUSI-TV (channel 51) is an independent television station in San Diego, California, United States. It is the sole property of locally based McKinnon Broadcasting Company. KUSI-TV's studios are located on Viewridge Avenue (near I-15) in the Kearny Mesa section of San Diego, and its transmitter is located southeast of Spring Valley. The station operates translator K12PO in Temecula (part of the Los Angeles market).

After a 15-year dispute over permit ownership that almost derailed the launch of the station on multiple occasions, KUSI began broadcasting in 1982 as a partnership between United States International University and McKinnon. It was the first independent station built in San Diego proper. Financial and accreditation problems at USIU led to the sale of its stake to McKinnon in 1990, with McKinnon exercising veto power to block any sale to another entity. McKinnon then started KUSI's news department, which has since grown to produce newscasts throughout the day.