Louisiana State University and Agricultural and Mechanical College, most often referred to as Louisiana State University, or LSU, is a public coeducational university located in Baton Rouge, Louisiana. The University was founded in 1853 in what is now known as Pineville, Louisiana, under the name Louisiana State Seminary of Learning & Military Academy. The current LSU main campus was dedicated in 1926, and consists of more than 250 buildings constructed in the style of Italian Renaissance architect Andrea Palladio, and occupies a 650-acre (2.6 km²) plateau on the banks of the Mississippi River.

LSU is the flagship institution of the Louisiana State University System, and the largest institution of higher education in Louisiana in terms of student enrollment. In 2011, the University enrolled nearly 24,000 undergraduate and over 5,000 graduate students in 14 schools and colleges. Several of LSU's graduate schools, such as the E.J. Ourso College of Business and the Paul M. Hebert Law Center, have received national recognition in their respective fields of study. Designated as a land-grant, sea-grant and space-grant institution, LSU is also noted for its extensive research facilities, operating some 800 sponsored research projects funded by agencies such as the National Institutes of Health, the National Science Foundation, the National Endowment for the Humanities, and the National Aeronautics and Space Administration.

LSU's athletic department fields teams in 20 varsity sports (9 men's, 11 women's), and is a member of the NCAA (National Collegiate Athletic Association) and the SEC (Southeastern Conference). LSU Tigers football began in 1893, with national championship wins in the 1958, 2003, and 2007 seasons. The University is represented on the field by its mascot, Mike the Tiger.