The University of Sassari (Università degli Studi di Sassari) is a public university located in Sassari, on the Italian island of Sardinia. Its foundation is linked to a bequest from Alessio Fontana, a Sardinian who served in the Imperial Chancellery of Emperor Charles V, and the institution held its official opening in May 1562, with early teaching entrusted to the Jesuits. It is therefore among the oldest universities in Sardinia and one of the historic universities of Italy. The university's Latin motto is 'Susceptum perfice munus.'

Regarded as a medium-sized institution, the university enrolls on the order of 13,000 to 18,000 students and is served by an academic body of roughly 700 teaching staff. After the reform of Italian higher education in the early 2010s, its historic faculties were reorganized into departments; English-language references describe it as organized into around a dozen departments covering areas such as agriculture, architecture and design, chemistry and pharmacy, law, veterinary medicine, biomedical sciences, economics and business, medicine, and the humanities and social sciences. Alongside its departments, the university runs research centres, specialist schools, and postgraduate programmes, and it maintains a historic botanical garden (Orto Botanico) in the city.

The University of Sassari is active in research across a broad range of fields, including biology, medicine, chemistry, environmental science, genetics, and the social sciences. It has featured in national assessments of Italian universities, having been rated among the leading medium-sized institutions in the country. The university takes part in international academic networks, including the Xarxa Vives d'Universitats (Vives Network) of universities in the western Mediterranean. Its facilities occupy an urban campus in the centre of Sassari, and its academic governance is headed by a rector.