Cardiff University is a public research university in Cardiff, Wales. Founded in 1883 as the University College of South Wales and Monmouthshire (University College Cardiff from 1972), it became a founding college of the University of Wales in 1893. It merged with the University of Wales Institute of Science and Technology (UWIST) in 1988 to form the University of Wales College, Cardiff (University of Wales, Cardiff, from 1996). In 1997 it received its own degree-awarding powers, but held them in abeyance. The college adopted the public name Cardiff University in 1999; in 2005 this became its legal name, when it became an independent university and began awarding its own degrees. Cardiff University is the only Welsh member of the elite Russell Group of research-intensive British universities.

Cardiff University is the third oldest university in Wales and contains three colleges: Arts, Humanities and Social Sciences; Biomedical and Life Sciences; and Physical Sciences and Engineering. The university has two Nobel Prize winners, 15 fellows of the Royal Society, 11 fellows of the Royal Academy of Engineering, seven fellows of the British Academy, 21 fellows of the Academy of Medical Sciences and 34 fellows of the Academy of Social Sciences among its academics.

In 2018–2019, Cardiff had a turnover of £537.1 million, including £116.0 million in research grants and contracts. It has an undergraduate enrolment of 23,755 and a total enrolment of 33,260 (according to HESA data for 2019/20) making it one of the ten largest UK universities. The Cardiff University Students’ Union works to promote student interests in the university and further afield.