Jacksonville University (JU) is a private university in Jacksonville, Florida, on the banks of the St. Johns River. The school was founded in 1934 as a two year college and was known as Jacksonville Junior College until 1958, when it shifted its focus to four-year university degrees and adopted its present name. It is a member of the Independent Colleges and Universities of Florida and is accredited by Southern Association of Colleges and Schools (SACS) and the Association to Advance Collegiate Schools of Business (AACSB). Its sports teams are known as the Jacksonville Dolphins.

The school was founded in 1934 by William J. Porter. Originally known as William J. Porter University, it began as a private two-year college. Since a permanent site had not yet been acquired, classes were held on the third floor of the First Baptist Church Educational Building in downtown Jacksonville. Sixty students were enrolled in Porter University's first year of operation.

The school changed its name to Jacksonville Junior College in 1935. It relocated three times over the next fifteen years, including a period in the Florida Theatre building, but the influx of GI bill students following the end of World War II made it necessary for the school to find a permanent location. In 1947 the administration purchased land in Jacksonville's Arlington neighborhood on which to establish the current campus. The first building was completed in 1950 and classes officially began. The same year the school received full accreditation as a two-year college from the Southern Association of Colleges and Schools (SACS).