Robert Allan Caro (born October 30, 1935) is an American journalist and author known for his biographies of United States political figures Robert Moses and Lyndon Johnson.

After working for many years as a reporter, Caro wrote The Power Broker (1974), a biography of New York urban planner Robert Moses, which was chosen by the Modern Library as one of the hundred greatest nonfiction books of the twentieth century. He has since written four of a planned five volumes of The Years of Lyndon Johnson (1982, 1990, 2002, 2012), a biography of the former president. Caro has been described as "the most influential biographer of the last century".

For his biographies, Caro has won two Pulitzer Prizes in Biography, two National Book Awards (including one for Lifetime Achievement), the Francis Parkman Prize, three National Book Critics Circle Awards, the Mencken Award for Best Book, the Carr P. Collins Award from the Texas Institute of Letters, the D. B. Hardeman Prize, and a Gold Medal in Biography from the American Academy of Arts and Letters. In 2010 President Barack Obama awarded Caro the National Humanities Medal.

Due to Caro's reputation for exhaustive research and detail, he is sometimes invoked by reviewers of other writers who are called "Caro-esque" for their own extensive research.