Captain Thomas Brown (1785 – October 8, 1862) was a British naturalist and malacologist.
Born in Perth, Scotland, he was educated at the Edinburgh High School. At the age of twenty, he joined the Forfar and Kincardine Militia, raising to the rank of captain in 1811. When he was quartered in Manchester, he became interested in nature, and edited Oliver Goldsmith's Animated Nature. After his regiment was disbanded he bought the Fifeshire flax mill. But this burned down before Thomas Brown had the opportunity to insure it and he then started to write books about nature for a living.
In 1840 he became curator of the Manchester Museum for twenty-two years.
He wrote several natural history books, a few dealing with conchology. He became a fellow of the Linnean Society, a member of the Wernerian, Kirwanian and Phrenological Societies, and president of the Physical Society. Material from his books was used by United States naturalist Thomas Wyatt for his book Manual of Conchology. Wyatt in turn hired Edgar Allan Poe to edit, compile, and "arrange" a revised, condensed, simplified, and less expensive version: The Conchologist's First Book (1839).
A species of sea snail, a marine gastropod, was named after him: Zebina browniana d'Orbigny, 1842.