Anna University (lang-ta????? ?????????????? ISO 15919:a??? palkalaikka?akam) is a university in Tamil Nadu state, India, offering higher education in Engineering, Technology and Allied Sciences.

Anna University was formed on September 4, 1978 as a unitary type of university. It integrated four technical institutions in the city of Chennai (previously known as Madras), including the College of Engineering, Guindy, established in 1794, and Madras Institute of Technology, established in 1949, which offered the first engineering degrees in India.

Perarignar Anna University of Technology (PAUT) was the original name used in 1978. In 1982 the current name of Anna University was adopted, removing the words "Perarignar" and "Technology". In December 2001, it was converted into an affiliating university, with almost all engineering colleges in the state of Tamil Nadu under its fold and also absorbing all the six government engineering colleges in Tamil Nadu as its constituent colleges. In all, it brought together about 250 engineering colleges in Tamil Nadu.

Since 13 February 2007 only the colleges situated in the districts of Chennai, Thiruvallur, Vellore, Kanchipuram, Thiruvannamalai and Vilupuram in Tamil Nadu have been affiliated to Anna University.

Anna University has four campuses (CEG, ACT and SAP in the main campus and MIT in Chromepet) having departments of Engineering, Technology and Applied sciences, and, under affiliation, about 108 self financing colleges and 1 Government College located in those districts.