Ronald Louis Ziegler (May 12, 1939 – February 10, 2003) was White House Press Secretary during United States President Richard Nixon's administration from 1969–1974 and Assistant to the President in 1974.

Ziegler was born in Covington, Kentucky. He worked on Nixon's unsuccessful California gubernatorial election in 1962 as a press aide. Ziegler became the youngest White House Press Secretary ever at the age of 29 in 1969. He was the White House press secretary for the Nixon administration during the political scandal. He initially described the break-in of the Watergate Hotel as a "third rate burglary," a phrase which has since lived in infamy.

Particularly in the period following the resignations of such senior administration officials as Bob Haldeman and John Ehrlichman, Ziegler became Nixon's closest aide and confidant in his administration. Ziegler defended the President until the bitter end, urging Nixon not to resign, but rather fight impeachment in the Senate. During the unfolding political scandal, Ziegler himself appeared at least 33 times before Congress. Despite Nixon's resignation in 1973, Ziegler remained very close to him and was even aboard the airplane that Nixon took to San Clemente as Gerald Ford was sworn into office.