The research library at the SAAO dates its existence to the arrival of the first Royal Astronomer in the 1820s. The SAAO Library is now the national library for astronomy and space science. The main collection is located in the Main Building at SAAO Cape Town, with a smaller collection at the observing site at Sutherland. The library has a unique richness of pre-twentieth century journals with the core astronomical journals starting at volume 1.

Library material can be checked out by SAAO researchers but library staff must have access to borrowed items at any time.