Western University of Health Sciences (WesternU) is a private university with its main campus in Pomona, California, and an additional medical school in Lebanon, Oregon. WesternU offers medical, dental, optometry, and podiatry degrees along with nursing, physician assistant studies, physical therapy, pharmacy, biomedical sciences, and veterinary medicine. With an enrollment of 3,814 students (2020-21), WesternU offers 21 academic programs in nine colleges.

Under the banner of WesternU Health, the university operates a variety of patient care facilities in California and Oregon. The Pomona and Portland (Oregon) campuses both include a medical center, dental center, eye care institute, pharmacy, and travel health center. WesternU-Pomona also is home to the Pet Health Center, which provides veterinary services. Dental services are offered at the Rancho Mirage campus, while a Los Angeles campus provides optometry services.

Several nonprofit organizations are based at the WesternU Pomona campus, including the Harris Family Center for Disability and Health Policy. The Center for Oral Health, moved from the Bay area to the WesternU Pomona campus in 2012. In 2015, the Southern California Medical Museum moved to the Pomona campus.

Founded in 1977, the first program at WesternU was its medical school, the College of Osteopathic Medicine of the Pacific (COMP). Since that time, the College of Veterinary Medicine opened in 2003, and colleges of dental medicine, optometry, and podiatric medicine opened in 2009. In 2011, the university opened an additional campus in Lebanon, Oregon, the College of Osteopathic Medicine of the Pacific - Northwest (COMP-Northwest). In 2015, the university's founding president, Dr. Philip Pumerantz, retired.

All of the programs at WesternU have professional accreditation and the university is accredited by the Western Association of Schools and Colleges. The medical school (COMP) is also accredited by the American Osteopathic Association's Commission on Osteopathic College Accreditation. The World Directory of Medical Schools lists the College of Osteopathic Medicine as a US medical school along with other accredited US MD and DO programs.