Amelia Alderson Opie was born in Norwich, England, the only child of James Alderson, a physician, and his wife Amelia Briggs.
Her mother died when she was a teenager, and she became her father’s housekeeper. She shared her father's radical principles and was an admirer of politician John Horne Tooke. She moved in intellectual circles that included William Godwin, Mary Wollstonecraft, Madame de Staël, and Elizabeth Inchbald; among her friends were Sarah Siddons, Anna Letitia Barbauld, Sir Walter Scott, and Richard Brinsley Sheridan. With no formal schooling, she began writing classical and Gothic dramas. In 1794, she published 15 poems in The Cabinet, a periodical started by Norwich reformers. In 1798, she married John Opie, a painter who encouraged her writing. Her literary career developed rapidly as she published poems, fiction, and songs, including the novels Father and Daughter (1801) and Adeline Mowbray (1804), based on the life of Mary Wollstonecraft. After her husband's death in 1807, Amelia left London and returned to her father’s home in Norwich, where she joined Elizabeth Fry in philanthropy, visiting workhouses, prisons, hospitals, and the poor. She promoted a refuge for reformed prostitutes and in 1840 represented Norwich at the national anti-slavery convention. She joined the Society of Friends in 1825 and stopped writing fiction, although she continued to contribute poems and prose pieces to literary annuals.