Olive Thomas (born Oliva R. Duffy;[1] October 20, 1894 – September 10, 1920) was an American silent-film actress, art model, and photo model.

Thomas began her career as an illustrator's model in 1914, and moved on to the Ziegfeld Follies the following year. During her time as a Ziegfeld girl, she also appeared in the more risqué show The Midnight Frolic. In 1916, she began a successful career in silent films and would appear in more than 20 features over the course of her four-year film career. That year she also married actor Jack Pickford, the younger brother of fellow silent-film star Mary Pickford.

On September 10, 1920, Thomas died in Paris five days after ingesting her husband's syphilis medication, mercury dichloride, that brought on acute nephritis. Although her death was ruled accidental, news of her hospitalization and subsequent death were the subject of speculation in the press. Thomas' death has been cited as one of the early scandals in Hollywood that was heavily publicized.