The Old University of Chicago was the legal name given in 1890 to the defunct school previously named "University of Chicago".

The school, founded in 1856 by Baptist church leaders, was called the "University of Chicago" (or, interchangeably, "Chicago University"). After years of financial struggle, the university's campus was badly damaged by fire, the school was foreclosed on by its creditors, its classes ceased in 1886, and it no longer admitted students. Rather than try to continue operations, its trustees decided in 1890 to change the school's name to the "Old University of Chicago" and allow the establishment of a new "University of Chicago".

The Northwestern University School of Law began as a department of the Old University of Chicago and transferred completely to Northwestern when Old UC folded. The Baptist Theological Union had formed a separate theological school in 1865 that would later be grafted into the new University as the University of Chicago Divinity School. While the present-day University of Chicago, which was established in 1891, is a separate legal entity and in a different location, it recognized Old University of Chicago alumni as its own and maintained a number of other continuities from its pre-1890 origins.