James F. Williams II is an African-American librarian, the Dean of Libraries at the University of Colorado at Boulder.

He holds a bachelor's degree in sociology from Morehouse College (1966) and a master's degree in library science from Atlanta University. His wife, Nancy Allen, is also a librarian, the Dean of Libraries at the University of Denver.

Since January 2003 he has been a member of the editorial board of the journal Portal: Libraries and the Academy. He is on the board of directors of the Association of Research Libraries and chairs the ARL's Strategic Direction Steering Committee on Influencing Public Policies for 2010-2013. He is also on the boards of visitors for the School of Information Sciences at the University of Pittsburgh and for the libraries at the Massachusetts Institute of Technology, a member of the Libraries' National Council of Washington University in St. Louis, and a trustee of the Denver Art Museum.

In 2002, Williams won the Melvil Dewey Medal of the American Library Association for his "distinguished service to the profession of librarianship".