Bontemps returned to graduate school and earned a master's degree in library science from the University of Chicago in 1943. He was appointed as head librarian at Fisk University in Nashville, Tennessee. During his time there, he developed important collections and archives of African-American literature and culture, namely the Langston Hughes Renaissance Collection. Bontemps was initiated as a member of the Zeta Rho chapter of Phi Mu Alpha Sinfonia fraternity at Fisk in 1954. He served at Fisk until 1964 and would continue to return occasionally.