Bon Ayer

The University of the Philippines Diliman (also called UPD; Filipino: Unibersidad ng Pilipinas Diliman), also referred to as UP Diliman or simply University of the Philippines (UP), is a public, coeducational, research university located in Diliman, Quezon City, Philippines. It was established on February 12, 1949, as the flagship campus and seat of administration of the University of the Philippines System, the national university of the Philippines.

As a member of the University of the Philippines System, it is the fourth oldest and is the largest constituent campus in terms of the number of degree-granting academic units, student population, faculty, and library resources. There are 27 degree-granting units on campus, accounting for 26,349 students of which, 17,117 are undergraduates. UP Diliman had a complement of 1,620 regular faculty in 2023, of whom 499 have doctoral degrees.

In addition to the units in the main campus, UP Diliman has extension programs in Angeles City, Pampanga (the Clark Freeport Zone area) and Olongapo, Zambales, as well as a marine laboratory in Bolinao, Pangasinan under the Marine Science Institute, and an satellite campus at Bonifacio Global City, Taguig. UP Diliman offers academic programs in 247 major fields. There are 70 programs at the undergraduate level, 109 programs at the master's level and 68 at the doctoral level.

The UP Diliman campus is also the site of the country's National Science Complex. Notable research units of UP Diliman centered at the National Science Complex include the Marine Science Institute (MSI), the National Institute of Geological Sciences (NIGS), the National Institute of Physics (NIP), the National Institute of Molecular Biology and Biotechnology (NIMBB), the National Institute for Science and Mathematics Education Development (NISMED), and the Computational Science Research Center (CSRC) which are all pioneers of scientific research and development in the Philippines. The Sentro ng Wikang Filipino, devoted to research on the intellectualization of the Filipino language, is also located in the campus.

A nationally important university, UP Diliman alumni include a Nobel Peace Prize laureate, Philippine presidents, chief justices of the Philippine Supreme Court, Philippine National Scientists, and Philippine National Artists, the most of any higher education institution. Taken as a single university distinct from other UP System campuses, UP Diliman is considered as the top institution of higher learning in the country, based on the reports published by the CWUR University Rankings and the U.S. News & World Report.

The Management Review Committee (MRC) was created by UP President Edgardo Angara in the 1980s to evaluate and recommend measures for the university's improvement. The report made by the MRC led to the decision of the Board of Regents to further decentralize the UP administration, declaring UP Diliman an autonomous unit and the system's flagship university on March 23, 1983. This also furthered the reorganization of some major units of the university, with the College of Arts and Sciences being split into three colleges: the College of Science, the College of Arts and Letters and the College of Social Sciences and Philosophy. UP Diliman was formally established as a constituent university on April 23, 1985, at the 976th Meeting of the U.P. Board of Regents.