Though there have been collections of music materials located in the old Music Conservatory and in the Memorial Library, an actual music library did not come into being until 1974 when it was established in the Marjorie Young Bell Conservatory of Music building.
In 1891 a large addition to the Mount Allison Ladies’ College building (known as the White House at that time) was erected to house a Conservatory of Music. A poster advertising a “popular concert” given by the pupils of the Conservatory “for the benefit of the Conservatory Musical Library” contributes anecdotal evidence that a small collection of printed music existed at that time and that it was housed in the Conservatory. The bulk of the Ladies’ College library collection was moved to the new Memorial Library in 1927, but the music collection including mostly recordings and housed in a room off of Beethoven Hall, remained in the Conservatory, and even in 1936 when responsibility for music instruction was transferred to the University, the music collection was retained in the Conservatory.
Over the years University library music holdings were enhanced by collections from a number of important donors. The Mary Mellish Archibald Memorial Library (MMAML) begun in 1901 was focused on folklore and folk music, and was housed in Memorial Library in a separate room with restricted access. Tunebooks, sheetmusic, recordings, and volumes of music were included in its acquisitions. While some Library recordings were on a long-term loan arrangement with the Music Conservatory, the textual items were held in the Memorial Library. In 1936, the Carnegie Corporation donated a ‘music set’ consisting of a large electric gramophone, some nine hundred 78 rpm recordings, and a collection of musical scores and books.  The set was held in what became known as the Carnegie Room in the Conservatory.
The music collection in the old Conservatory was moved in 1966 to the newly built Marjorie Young Bell Conservatory of Music. Music materials were ultimately amalgamated on the ground floor of the building and contained some of “the main holdings of the University’s collection of records and music scores”, and included “eight turntables, both cartridge and reel type, for individual and group listening."  The collections were bolstered, probably at this time, with scores and printed music stamped the “Department of Music Library”, and many signed or stamped with the names of Ethel Peake, Allison G. Patterson, and others, as well as many more either stamped or bookplated, “Mary Mellish Archibald Memorial”. The single room Music Library was expanded to another room on the other side of the corridor to accommodate stack shelving.
On 19 October 1974, the music library was officially inaugurated as the Alfred Whitehead Memorial Music Library. Whitehead was the highly regarded former head of the Department of Music. Born in Peterborough, England, he had moved to Canada in 1912 and served as Assistant Director of Music and Professor of Organ and Harmony at the Mount Allison Conservatory from 1913 to 1915. He then furthered his own education, receiving a Bachelor of Music from the University of Toronto in 1916 and a doctorate in music from McGill University in 1922. From there, he was the Organist at the Christ Church Cathedral in Montreal from 1922 to 1947. He also began writing music around 1923, and at his death had more than 400 compositions credited to his name. Dr. Whitehead returned to Mount Allison as Dean of Music in 1947. In 1953, he retired to Amherst, Nova Scotia, though from 1953 to 1965 he was organist at the Trinity St. Stephen’s Church in Amherst. He received an honorary doctor of law degree from Mount Allison University in 1958, and from Queen’s University in 1970.
The new music library was described in an article written at the time of the opening:
[The Alfred Whitehead Memorial Music Library] houses an expanding collection (about 16,000 volumes in 1974) of music materials. One special feature is its collection of Canadian music, including scores, books, periodicals and approximately 300 recordings. This compilation forms an important resource centre for Canadian music for the Atlantic provinces. 
Particular strengths in the collections sometimes resulted from research interests; George Proctor, for instance, was able to use the collections for researching his monographs, Sources in Canadian music, and Canadian music in the twentieth century. By 1974 librarian Gwen Ebbutt Creelman was designated responsible for music, followed by Mary Greenwood in 1985. Peter Higham began his tenure as music librarian in 1987 and continues to the present.
The Alfred Whitehead Music Library underwent an expansion and renovation in 2002 which enabled an improved layout, along with better lighting, more shelf space, and more work space for students. It is a fully functioning branch of Mount Allison University Libraries and Archives and has one of the strongest collections in Atlantic Canada. The holdings currently include more than 23,000 titles of catalogued items: printed music and scores, books about music, journals, electronic databases, recordings and music streaming and other audio-visual materials. Additionally, there are sizable collections of in-house recordings and sheet music.