The Seoul National University Library is the largest repository of modern literature in Korea, and also holds the largest collection of rare and old books among university libraries in the country.

The Rare and Old Book Collections unit of the SNU Library manages the collections of the former Keijō Imperial University Library and other rare and old books acquired by the library since its establishment in 1946. Over 410,000 books and non-books are currently managed and preserved, and about 210,000 of those items are modern publications from the Japanese colonial period and the Korean War era.

In addition, the Rare and Old Book Collections unit has organized and manages major individual collections representing the academic history of SNU. Starting from the Ilsa Collection in 1953 to the addition of the Kwon Young-min Collection in 2023, a total of 15 collections have been arranged. More than 1,000 items are donated annually by distinguished researchers, expanding the library's holdings and enriching SNU's academic heritage.

Notable items in the collection include 송조표전총류 (National Treasure No. 150), printed with the Gyemi-ja type (계미자, 癸未字) during the reign of King Taejong of the Joseon Dynasty. The library also houses three national treasures, 15 treasures, three state-registered cultural heritage items, and four UNESCO Memory of the World items, including materials on long-term loan at the Kyujanggak Institute. Equipped with temperature and humidity monitoring systems, the Rare and Old book Collections unit works to ensure the safe preservation and management of its collections through restoration and conservation of materials, digital content development, and environmental improvement projects. Furthermore, it actively pursues the societal sharing of its resources and transformation into a "library-archive-museum" (Larchiveum) by collecting records, publishing academic works, and hosting exhibitions. Additionally, starting with the Park Wansuh Archive, which is scheduled to be established in the second half of 2025, we will pave the way for knowledge to flow from the past to the future by systematically accumulating, researching, and preserving the records of the Seoul National University community.