The University of Illinois at Urbana-Champaign, also known as UIUC and the U of I (the officially preferred abbreviation), is the largest campus in the University of Illinois system. It is highly ranked in library and information science, engineering, computer science, physical sciences, advertising, psychology, agriculture, and accounting. The campus is divided almost exactly between the cities of Urbana and Champaign. The university is composed of 18 colleges and institutes that offer more than 150 programs of study. There are approximately 29,000 undergraduates and 10,000 graduate students at Urbana-Champaign.

A nationally acclaimed research center, UIUC is the site of the National Center for Supercomputing Applications, which created the first graphical Web browser, Mosaic and Telnet. The University also has the third largest academic library, and the largest public engineering library (Grainger Engineering Library) in the country. The Daily Illini is the (unofficial) student newspaper. In 1952 the University built the ILLIAC (Illinois Automatic Computer), the first computer built and owned entirely by an educational institution. UIUC is also the site of the Department of Energy's Center for the Simulation of Advanced Rockets, an institute which has employed graduate and faculty researchers in the physical sciences and mathematics in some of the most advanced research in the field. This history of excellence continues into the 21st century, both with the recent opening of the Siebel Center for Computer Science, the most technologically advanced academic facility to date, and the anticipated opening of the Institute for Genomic Biology in 2006.

The symbol of the University is a Native American figure, Chief Illiniwek, which has sparked significant controversy. Critics of the symbol claim that it is a racist stereotype, while supporters claim that it is unoffensive and is a source of pride for many students. The University is deeply divided on this issue; while some of the faculty have condemned the symbol, the administration is largely supportive of it.

The University is one of the few educational institutions to own an airport. The University owns and operates Willard Airport, named for former University of Illinois president Arthur Cutts Willard. The airport for completed in 1945 and began service in 1954. Willard Airport is home to many University research projects and the University's acclaimed Institute of Aviation.

See: UIUC College of Engineering

11 alumni and nine professors from U of I have won the Nobel Prize.