Mary Ellen Richardson was a solicitor and educationist.
Little is known of her early life, but by the 1870s she had a legal practice in the Inns of Court with England's first female solicitor, Eliza Orme. She became honorary secretary of the Association to Promote Women's Knowledge of Law in 1878.
She lived in the same house on Gray's Inn Road as Jane Chessar, a pioneering educationist who was elected onto the London School Board in 1873. When Chessar was forced to stand down from the board at the 1879 election, Richardson was persuaded to be a candidate by their mutual friend, Elizabeth Garrett. She served two three-year terms as one of the representatives of the Southwark Division, retiring from public life in 1885.
Richardson entered business as the proprietor of Bedford Park Co-operative Store before moving to Cornwall in 1894.