The Longwood Public Library began in a one room building that was formerly the Coram School. Mrs. Evelyn Holschuh Brown is credited as the library founder. A provisional charter to establish library services was granted in June 1953. Originally called the "Coram Public Library", the library opened its doors in the little school house on November 24, 1953. During the first year the library struggled to operate with a volunteer staff and a budget $1,000. Although the Library was open for only 8 hours per week and contained only 250 donated books, annual circulation exceeded 1,000 items. By 1958 the library's area of service was expanded to 54 square miles including the communities of Middle Island, Ridge, Yaphank, Lake Panamoka, Coram, Gordon Heights, North Medford and North Shirley.
In order to have a much better location, the library rented space in the former Billy Blake Shopping Center on Middle Country Road in Middle Island (now WalMart) and opened its new 3,800 square foot facility at the northeast corner of the store on December 2, 1971. An architect was retained to design and supervise the renovation of the larger adjacent quarters. Renovations were completed by 1978 and library operations continued without interruption during this move.
Working with an architect to meet both current and future building needs, on April 16, 1986, the Board of Trustees finalized its plan to purchase land and construct a new library at the southwest corner of Middle Country Road and Old Yaphank Road in Middle Island. This proposal was overwhelmingly approved by a community vote of 1360 to 200. On July 1, 1987 the library's name was changed to Longwood Public Library to reflect its role serving the entire school district population. On November 3, 1988 the first permanent library structure in the community's history was opened to the public.
Longwood Public Library is a member of the Long Island Library Resources Council.