Public library service in Moline has had a long history. The first Board of Trustees was appointed on September 18, 1872 , only twenty days after Moline became a city. The first library building, which was located at fifteenth street and third avenue , opened its doors on June 12, 1873 . The present Downtown building has been in operation since January 26, 1904 .

Construction of the Main Library would not have been possible without a contribution of $40,000 from industrialist Andrew Carnegie. W.A. Jones, a Moline newspaperman, had written to Carnegie asking that Moline be placed on the list of towns to be given funds for library construction. Carnegie replied, saying that if Moline would provide a site and not less than $3,700.00 in support per year, he would give Moline $37,000.00 (the amount was later raised to $40,000.00). Architects F.F. Borgolte and William Wells were chosen, and a site purchased from S.H. Velie for $10,000.00. The total cost of the new building and its furnishings was $65,000.00, including the cost of the site; it was constructed by Peter Peterson. The cornerstone was laid on May 2, 1903 .

The new building had an opening celebration on January 26, 1904 . The program consisted of an open house, tour and explanation of the building, but no oration. The Library opened for business the next day. At the time of the opening, the areas of the library were used differently than they are used today. The basement had two public areas -- to the right was the Men's Smoking and Reading Room and to the left a room designed to be used in the future as a children's department. On the main floor, the librarian's desk was opposite the doors with the stacks immediately behind the desk. To the right was the General Reading Room, furnished with eight long oak tables. The large room to the left was the Children's and Ladies' Room. These rooms, the unused room downstairs, and the Assembly Hall upstairs had large working fireplaces. The office to the right of the librarian's desk was the Reference Room, and the one to the left a private office. The second floor had a large Assembly Hall to the left, the center room was designed for art exhibits, and the two rooms to the right were set aside for committee work and general meetings. In 1954, the Committee Room became the Katherine Deere Butterworth Room (local history and genealogical research.)

In 1964 a major remodeling of the Library was completed in order to improve the deteriorating structure, and to enlarge space for the book collection. This remodeling included the installation of an elevator and the library has subsequently been made additionally accessible to the disabled by the installation of an exterior ramp, handicapped restroom and automatic doors. A complete renovation of the second floor provided space for a Film and Fine Arts Department. The Children's Room in the basement was also enlarged. Since 1964, the Library has undergone additional changes in collection organization and facility improvement. The book collection was moved several times and in 1986, new carpeting was laid and interior painting was completed. In 1987, the 32 year old Quad-City/Scott County Film Cooperative administered by Moline Public Library as disbanded and the over 800 16mm films and inspection equipment which had been housed at the Main Library were auctioned to the highest bidder.

A fund drive was begun in 1980 in order to build a branch library in the Southeast section of the city, which was being served from a small temporary structure. The successful drive raised $1.1 million and construction was begun in March 1982. Completed in 1983 the Southeast Branch houses a large Children's Department, and an Adult Services Department emphasizing current and popular materials.

In April 1986, The Moline Public Library began using CLSI, an automated library system. In November 1987, the City of Moline adopted a resolution to accept the bequest of Helen Bertha Reher on behalf of the Moline Public Library to establish the Reher Art Gallery in memory of her parents and to fund art related activates and materials at both library facilities. The resolution specified that expenditure of the bequest be based upon a five year plan to obtain additional funding through grants and gifts to fulfill the intent of Ms. Reher's bequest.