The University of the Philippines (UP; Filipino: Unibersidad ng Pilipinas or Pamantasan ng Pilipinas) is a state university system in the Philippines. It is the country's national university, as mandated by Republic Act No. 9500 (UP Charter of 2008), which grants it institutional autonomy.

The University of the Philippines was established by the American colonial government on June 18, 1908, through the enactment of Act No. 1870 by the 1st Philippine Legislature. It was envisioned as the country's premier institution of higher learning, with a mandate to provide "advanced instruction in literature, philosophy, the sciences, and the arts and to give professional and technical training," regardless of "age, sex, nationality, religious belief, or political affiliation."

The university's founding academic units were established primarily in Manila and Los Baños, Laguna. UP later expanded to Quezon City in 1949, where UP Diliman became the nucleus of the entire university system. Today, the university consists of eight autonomous constituent universities (CUs) and one autonomous college: UP Diliman, which hosts the system's central administration; UP Los Baños; UP Manila; UP Visayas; UP Open University; UP Mindanao; UP Baguio; UP Cebu; and UP Tacloban, which are distributed across 17 campuses nationwide.

In the late 19th century, many Filipinos pursued higher education in Spain and other European universities, highlighting the absence of a comparable institution in the Philippines that could provide advanced instruction across various fields. To address this need, the University of the Philippines was established on June 18, 1908, through . Act No. 1870 of the First Philippine Legislature, otherwise known as the "University Act". The law specified the function of the university, which is to provide advanced instruction in literature, philosophy, the sciences and arts, and to administer professional and technical training. Judge Newton W. Gilbert acted as president of the university since its establishment in 1908.

The university began with the organization of its first academic units. The earliest established in 1909 were the College of Agriculture and the School of Fine Arts. These were soon followed in 1910 by the Colleges of Veterinary Medicine, Liberal Arts, Engineering, and Medicine and Surgery. The College of Law, founded in 1911, was the last of UP’s founding academic units. Although the College of Medicine and Surgery officially became part of UP in 1910, it had already opened for instruction in 1907. This was in accordance with the University Act of 1908, which provided that the Philippine Medical School would be incorporated into UP as the College of Medicine and Surgery once two or more colleges had been established.

The academic units were originally located in different sites. The College of Agriculture was established in Los Baños, at the foot of Mount Makiling, while the School of Fine Arts opened in a private property on R. Hidalgo Street in Quiapo, Manila. The remaining units were also based in Manila: the College of Medicine and Surgery on Herran Street (now Pedro Gil Street), the College of Veterinary Medicine in Pandacan, the College of Liberal Arts held classes on several locations including the Philippine Normal School, the College of Engineering on the site that later formed part of the Padre Faura campus, and the College of Law in a private property on Isaac Peral Street (now United Nations Avenue). The School of Forestry was likewise established in 1910 in Los Baños. At the time, UP President Murray Bartlett declared that as a “University for the Filipino,” the institution must be “supported by the people’s money,” guided by a charter framed by the people’s representatives, and sustained by “the confidence and sympathy of the people.”

Plans to transfer academic units from the Manila campus to a new site were formally raised in 1937 to accommodate the university’s growing needs, with President Manuel L. Quezon initiating the idea. Among the proposals considered was the relocation of certain Manila units to the Los Baños campus, though this was deliberated among university officials. By 1938, a property in Marikina (now part of Quezon City) owned by the Philippine National Bank emerged as a leading option. Eventually, the Board of Regents approved the establishment of a new campus in Diliman, Quezon City, where the university acquired a 493-hectare lot. Construction of the Diliman campus began in 1939 but was interrupted by the outbreak of World War II.

During World War II, most of its colleges had to be closed except the Colleges of Medicine, Pharmacy, and Engineering. Meanwhile, the Japanese Imperial Army occupied three Diliman campus buildings: the College of Liberal Arts Building (now Benitez Hall) and the Colleges of Law (now Malcolm Hall) and Business Administration Building. The Japanese also occupied the campus of the College of Agriculture in Los Baños. U.P. President Bienvenido Ma. Gonzalez sought a grant of ₱ 13 million from the US-Philippines War Damage Commission. A massive rehabilitation and construction effort was executed during the post-war years. For the first time, an extensive Diliman campus master plan and map were created in 1949. More buildings were built across the Diliman campus landscape: the University Library (Gonzalez Hall), the College of Engineering (Melchor Hall), the Women's Residence Hall (now Kamia Residence Hall), the Conservatory of Music (Abelardo Hall and now the College of Music), the Administration Building (Quezon Hall), and the U.P. President's Residence. Most colleges and administration offices were temporarily housed in huts and shelters made of sawali and galvanized iron.