Frank Leslie's Illustrated Newspaper, later renamed Leslie's Weekly, was an American illustrated literary and news magazine founded in 1855 and published until 1922. It was one of several magazines started by publisher and illustrator Frank Leslie.

Throughout its existence, the weekly provided illustrations and reports—first with wood engravings and daguerreotypes, later with more advanced forms of photography—of wars from John Brown's raid at Harpers Ferry and the Civil War until the Spanish–American War and the First World War.

Surviving issues today are highly prized as collectors' items for vividly depicting American life during the seven decades of its existence. Many distinguished writers were featured in its pages.