St. John Bosco High School (SJBHS) is a Salesian, all-boys college preparatory high school located in Bellflower, California, and is operated by the San Francisco Province of the order.

Bellflower is a city located in southeast Los Angeles County, California, in the Los Angeles metropolitan area. It was founded in 1906 and incorporated on September 3, 1957. As of the 2020 census, the city had a total population of 79,190, up from 76,616 at the 2010 census. This made it the 65th most densely populated city in the United States, of cities over 50,000 residents.