The University of Texas Medical Branch (UTMB) is a component of the University of Texas System located in Galveston, Texas, United States, about 50 miles (80 km) southeast of Downtown Houston. It is an academic health center with 11,000 employees and a medical school that is the oldest in Texas. In February 2015 it had an endowment of $513 million.

Established in 1891 as the University of Texas Medical Department, UTMB has grown from one building, 23 students and 13 faculty members to more than 70 buildings, more than 2,500 students and more than 1,000 faculty. It has four schools, three institutes for advanced study, a comprehensive medical library, three on-site hospitals (including an affiliated Shriners Hospital for Children), a network of clinics that provide primary and specialized medical care and numerous research facilities.

UTMB's primary missions are health sciences education, medical research (it is home to the Galveston National Laboratory) and health care services. Its Emergency Room at John Sealy Hospital is certified as a Level I Trauma Center and serves as the lead trauma facility for a nine-county region in Southeast Texas; it is one of only three Level I Trauma centers serving all ages in Southeast Texas.

In fiscal year 2012, UTMB received 20 percent of its $1.5 billion budget from the State of Texas to help support its teaching mission, hospital operation and Level 1 Trauma Center; UTMB generates the rest of its budget through its research endeavors, clinical services and philanthropy. It provides a significant amount of charity care (almost $96 million in 2012), and treats complex cases such as transplants and burns.

In 2003 UTMB received funding to construct a $150 million Galveston National Biocontainment Laboratory on its campus, one of the few non-military facilities of this level. It houses several Biosafety Level 4 research laboratories, where studies on highly infectious materials can be carried out safely.It has schools of medicine, nursing, allied health professions, and a graduate school of biomedical sciences, as well as an institute for medical humanities. UTMB also has a major contract with the Texas Department of Corrections to provide medical care to inmates at all TDC sites in the eastern portion of Texas. UTMB also has similar contracts with local governments needing inmate medical care.