The school was formed by an association of pioneering women physicians Sophia Jex-Blake, Elizabeth Garrett Anderson, Emily Blackwell and Elizabeth Blackwell with Thomas Henry Huxley. The founding was motivated at least in part by Jex-Blake's frustrated attempts at getting a medical degree at a time when women were not admitted to British medical schools. Other women who had studied with Jex-Blake in Edinburgh joined her at the London school, including Isabel Thorne who became honorary secretary when Jex-Blake withdrew in 1877 and went to start medical practice in Edinburgh where she would found the Edinburgh School of Medicine for Women in 1886.
The 1876 Medical Act was introduced into the British Parliament by an MP named Russell Gurney, and received Royal Assent the same year. The bill extended the 1853 Medical Act to allow all examining authorities to grant registration to physicians regardless of gender.
In 1877 an agreement was reached with the Royal Free Hospital that allowed students at the London School of Medicine for Women to complete their clinical studies there. The Royal Free Hospital was the first teaching hospital in London to admit women for training.
Elizabeth Garrett Anderson was Dean (1883-1903) while the school was rebuilt, became part of the University of London and consolidated the association with the Royal Free Hospital. In 1896 the School was renamed the London Royal Free Hospital School of Medicine for Women.
In 1894 a well known Asian Indian feminist Dr. Rukhmabai qualified in medicine after attending the London School of Medicine for Women. The number of Asian Indian women students increased and by 1920 the school in cooperation with the India Office opened a hostel for Asian Indian women medical students.