William Curtis (11 January 1746 – 7 July 1799) was an English botanist and entomologist, who was born at Alton, Hampshire.
Curtis began as an apothecary, before turning his attention to botany and other natural history. The publications he prepared effectively reached a wider audience than early works on the subject had intended. At the age of 25 he produced Instructions for collecting and preserving insects; particularly moths and butterflies.
Curtis was demonstrator of plants and Praefectus Horti at the Chelsea Physic Garden from 1771 to 1777. He established his own London Botanic Garden at Lambeth in 1779, moving to Brompton in 1789. He published Flora Londinensis (6 volumes, 1777–1798), a pioneering work in that it devoted itself to urban nature. Financial success was not found, but he went on the publish The Botanical Magazine in 1787, a work that would also feature hand coloured plates by artists such as James Sowerby, Sydenham Edwards, and William Kilburn.