Mary Eliza Mahoney (May 7, 1845 – January 4, 1926) was the first African-American to study and work as a professionally trained nurse in the United States. In 1879, Mahoney was the first African American to graduate from an American school of nursing.

In 1908, Martha Minerva Franklin and Adah B. Thoms, two of Mahoney's colleagues, met in New York City to found the National Association of Colored Graduate Nurses (NACGN). Mahoney, Franklin, and Thoms worked to improve access to educational and nursing practices and to raise standards of living for African-American registered nurses. The NACGN played a foundational role in eliminating racial discrimination in the registered nursing profession. An increase in the acceptance of Black women into notable medical positions, as well as the integration of the NACGN with the American Nurses Association, prompted the dissolution of the organization in 1951.

Mahoney received several honors and awards for her work. She was inducted into the American Nurses Association Hall of Fame in 1976 and the National Women's Hall of Fame in 1993.