Established in 1845, the Library is and has been synonymous with the Society. It has almost 11,000 volumes including rare and valuable books and 117 title of Journals. The Library is also in possession of extremely rare collections of manuscripts of national interest belonging to the 17th and 18th centuries collected over two centuries.
The Library is primarily for the use of the members of the Society. Other readers may be admitted, by prior appointment, for a limited period of time. Though it is mainly a reference library, members are allowed to borrow two books at a time from the lending section.
Access to the collections is restricted, the readers should first identify the required books and journals from the catalogue and place the requisition with the Assistant Librarian who will then provide the book to the table of the reader if it is available.
The Library covers all areas which come under the objectives of the society, which are to institute and promote inquiries into the History, Religions, Language, Literature, Arts, Sciences and Social Conditions of the present and former peoples of the Island of Sri Lanka and connected cultures.