Lakehead University is a public research university with campuses in Thunder Bay and Orillia, Ontario, Canada. Lakehead University, shortened to 'Lakehead U', is non-denominational and provincially supported. It has undergraduate programs, graduate programs, the Bora Laskin Faculty of Law, the only internationally accredited (AACSB) business school in northern Ontario, and is home to the western campus of the Northern Ontario School of Medicine.

Lakehead has more than 45,000 alumni. The main campus in Thunder Bay has about 7,900 students. As of September 2006, a new permanent extension campus in Orillia, located about 150 kilometres (93 mi) north of Toronto, has about 1,400 students.^{[citation needed]}

Lakehead University evolved from Lakehead Technical Institute and Lakehead College of Arts, Science, and Technology. Lakehead Technical Institute was established in response to a brief that outlined the need for an institution of higher education in northwestern Ontario. It was established on June 4, 1946, by an Order-in-Council of the Province of Ontario. Classes commenced in January 1948, in temporary rented quarters in downtown Port Arthur. In September of that same year, the first university courses were added to the curriculum.

Lakehead College of Arts, Science and Technology was established by an Act of the Ontario Legislature, proclaimed on August 1, 1957. Years later, the original Lakehead College of Arts, Science and Technology Act was amended to grant the college authority to establish new faculties, and confer degrees in arts and sciences.

The Lakehead University Act was given royal assent on June 22, 1965, and came into force on July 1, 1965. The Lakehead College of Arts, Science and Technology, thereafter known as "Lakehead University", was continued under this new charter. The first degrees were conferred on May 5, 1965. The first university chancellor was Senator Norman McLeod Paterson.

The original college site comprised about 32 hectares of land in south-west Port Arthur, Ontario. From 1962 to 1965, an additional 87 hectares of adjoining land was purchased in anticipation of future expansion. The first building was opened in 1957.

In 2005 the Northern Ontario School of Medicine (NOSM) was formed as a joint initiative between Lakehead University and Laurentian University in Sudbury organized within the Faculty of Medicine of both Laurentian (East Campus) and Lakehead (West Campus) universities. The medical school has multiple teaching and research sites across Northern Ontario, including large and small communities. Students are given a choice of attending either one of the two main NOSM campuses. NOSM is the only Canadian medical school to be established as a stand-alone not-for-profit corporation, with its own Board of Directors and corporation bylaws.

A new law school was established; the faculty accepted its first students in 2013. The program is housed in the former Port Arthur Collegiate Institute. In 2014 it was named the Bora Laskin Faculty of Law, after the fourteenth Chief Justice of Canada.