This library building was built with funds from Thomas Cochran, his sister Louis Cochran Savage and in the names of his brothers William, Class of 1895, and Montcreiff, Class of 1900 for a total of $500,000. The library was again designed by Charles A. Pratt and Thompson Starrett Co. the builders. It was named for Phillips graduate, Oliver Wendell Holmes Class of 1825, doctor and poet.

The library contains several reading rooms, the Garver Reading Room, Freeman Room, David Poynter Room (1946) and the contemporary designed James S. Copley Wing built in 1959. Ground breaking for a new addition to the rear of the library began on April 30, 1987. Designed by Shepley, Bulfinch, Richardson, and Abbot. The Copley wing was removed at this time to accommodate the new addition. The cost was $10,500,000. and the dedication was held on May 19, 1989.