METU Library was first housed in a small room in the General Directorate of Retirement Fund's building in Milli Müdafaa Street in Bakanlıklar, and was started to serve with a small collection in Architecture which was gifted by United Nations, in October 1956. Furuzan Olşen (October 14, 1957) and Solmaz İzdemir, founders of the METU Library, were appointed as librarians. Natelle Isley, an expert from UNESCO, was appointed as the Library Director on January 4, 1958 with a biref to improve the Library.

The Library's collection started growing thanks to donations of books from the British and USA governments. Donald Redmond, also an expert from UNESCO, replaced Natelle Isley as Library Director in July 1959. The first financial aid from the United Nations was on October 26, 1960, and continued for 4 years. This aid, which amounted to $25,000 per year was extremely important for the improvement of the Library during the initial period after its establishment. The third director of the Library D.R. Kalia, again an expert from UNESCO, worked until the end of 1961. On March 19, 1962, CENTO provided £1,564 to the Library for the purchase of books and journals.

William W. Bennett, fourth and the last expert from UNESCO, was appointed as Library Director on July 9, 1962. The Library developed rapidly into a real library. Mr. Paul Wasserman, Library Director at Cornell University, visited in September 1962, and prepared a report about the development of the Library, as a result of which $30,500 from the AID/ Cornell project was donated to the Library. Aid to the Library continued in those days. The German government donated a collection to the Library on July 9, 1963. The Library's collection reached to 50,000 volumes with the donation of 805 books and 605 journals from the American People to the People Programme on April 26, 1964, 220 books from the J.F.Kennedy Memorial Library on November 28, 1964, and 1,000 books from the British government on 30 June,1965. W.W. Bennett worked as the Library Director until 1965.

The Library moved to the current campus on 15 September 1963, and served in the Architecture Faculty's building until the main Library building was completed. Behruz Çinici, architect of the METU Library building, visited the USA in April 1963 to study on library buildings. In the same year Dr. A.F. Kuhlman came to Turkey and worked in METU for one month to contribute to the studies concerning the structure of the Library building. The first part of the current Library building was completed in 1967 and second part of the building was completed in 1975. Solmaz İzdemir, who was the Associate Director of the Library for many years, died on 26 September 1979, and her name was given to the conference and cinema hall in memory of her.

Furuzan Olşen was appointed as the Library Director in 1965, and worked until the retirement in 1981. Dr. Tekin Aybaş replaced Furuzan Olşen after her retirement and worked until 1988. Between 1988 and 1993, Filiz Çermen was the Library Director.

Prof. Dr. Bülent Karasözen replaced her in 1993 and worked until 2007 as the Library Director. Some of the most important acts during his management were the transition to the process of library automation, developing the e-book and e-journal collections, and establishing and developing the Anatolian University Libraries Consortium, ANKOS.

As of February 14, 2007, Cevat Güven was appointed as the Library Director.

METU Library has one of the largest collections in Turkey with it's 406.591 books, 76.630 e-books, 173.767 bound periodicals, 1.249 journal subscriptions, 56.158 e-journal subscriptions, and 16.222 dissertations according to the indicators in 2009.

The book collection is arranged according to the Library of Congress Classification System, in which subjects are arranged alphabetically.Collections are predominantly in English but also in Turkish. All printed materials are on open access in the reading halls except dissertations, TSE standards, bound periodicals belonging 1989 and before, and the stacks collection.