The BCHS Research Library is unique in New York City. It houses an extensive collection of historical information on The Bronx, including books, reports, pamphlets, microfilms, etc. Located in the head-quarters of BCHS across the street from the Valentine-Varian House, the library is intimate and accessible. It is a major resource center for high school and college students, journalists, business and government researchers and scholars who have a professional need–or curiosity–to learn more about The Bronx.

In 1974, the collection of historical material grew considerably when BCHS assumed responsibility for nearly a million items which were then established as The Bronx County Archives. The archives contain original documents, manuscripts, books, maps and city directories going back to pre-Civil War days, covering not only Bronx history but also the history of New York City and Westchester County.  The Bronx County Archives is located next door to the Research Library building. The Research Library and Archives also boast an enormous collection of 19th and early 20th century photographs, prints and postcards of The Bronx.  The historic images include 75,000 photographs and slides, 4,000 glass negatives and 1,500 postcards and stereocards. There is also an important collection of periodical literature and publications, beginning with the first issue of The Bronx Home News from 1907. Finally, there is a special collection of material on the life and works of Edgar Allan Poe.

One advantage the BCHS library offers researchers is direct access to the collection. They can look through historic personal papers, listen to tapes in the oral history archives, view videos or study the old photographs. The library has an easy to use cross indexed card file and a quiet, personal atmosphere.