On May 25, 1905, in Warrenton Virginia, Hayes Joseph and Bertha (née Ball) Burnett welcomed their first child, a daughter, who they named Dorothy Louise. The family would soon move to a predominately White-populated neighborhood in Montclair, New Jersey. Hayes, a physician, and Bertha, a tennis champion who was essential in the creation of the New Jersey Tennis Association, emphasized the value and importance of education to Dorothy and her three siblings. Having attended racially-mixed public schools, in 1923, Dorothy entered Minor Normal School in Washington, D.C. Burnett selected to attend Minor Normal School after her graduation from high school because the institution was renowned for educating African-American women, especially in training them to enter the field of teaching.
During her time of study at Miner Normal School, Dorothy, a bibliophile, was presented with an opportunity that would prompt her to abandon a future career as a teacher. In 1925, her spur-of-the-moment decision to briefly substitute for a librarian who was out on sick leave transformed what the rest of her life. The substitution developed into a year-long assignment and it greatly inspired her to seek a career in library science.
In 1926, Dorothy Burnett transferred to Howard University, a historically Black university located in Washington, D.C. After earning her Bachelor of Arts from Howard University in 1928, she joined the library staff at Howard. She also matriculated graduate school at Columbia University in the City of New York, an Ivy League university.
While at Columbia University, she attained a position as a librarian at the Harlem branch of the New York Public Library, presently known as the Schomburg Center for Research in Black Culture. While working at the esteemed library branch that focused on Africa Diaspora culture, she met artist James A. Porter. Porter was conducting research on African-American artists who had been overlooked and/or omitted from American history and culture. Building beyond their professional interests, Porter courted Burnett.