The beginnings of what is known as the Colombo Public Library were in 1925 when the Colombo free library was opened on August 10. It was on a resolution moved in the Municipal Council by E. W. Jayawardena that the library was established.
There were two libraries at the time, namely the Colombo Library and the Pettah Library. The Colonial Secretary at the time, Sir Cecil Clementi called a meeting of subscribers to both libraries and it was agreed to hand over their books to the new library which was to be run as a department of the Municipal Council.

By that time, the Colombo Library had been in existence for over a century, having been founded in 1813. Called 'The United Service Library' it was exclusively for the use of civil and military officers of the Government stationed in Colombo and was housed in a building opposite the Queen's House (presently the President's House). A few years later the Burghers of Colombo opened a library in Pettah and called it the 'Colombo Pettah Library.' Pettah was the residential area of the Burghers who moved over from Fort when it became too busy and noisy.

The Public Library was housed in one of the oldest mansions called 'Sirinivasa,' in Edinburgh Crescent owned by Mudaliyar Sri Chandrasekera for 55 years, until a more spacious building was constructed at the present site at Vihara Maha Devi Park. The earlier building is now the official residence of the Mayor of Colombo.

The Colombo Museum Library was also one of the early libraries in the city. The founder of the Museum, Governor Sir William Gregory (1872-77) was instrumental in promoting the Museum library too and ordered many works of reference on natural history and oriental literature. These along with the library of the Royal Asiatic Society Ceylon Branch, which was housed in the Museum, formed a valuable reference library particularly for research students.