Robert Livingston Gerry, III (born 20 September 1937) is a businessman and petroleum industry executive.
Son of Robert L. Gerry, Jr. Grandson of prominent Thoroughbred horse breeder Robert L. Gerry, Sr. Great nephew of U.S. Senator Peter G. Gerry. Great nephew of Governor W. Averell Harriman. Great nephew of E. Roland Harriman. Great grandson of railroad baron Edward Henry Harriman. (Grandmother was EH Harriman's daughter, Cornelia Harriman, who married Robert L. Gerry, Sr.) Great-great-great grandson of Elbridge Gerry, signer of the Declaration of Independence. Nephew of horse breeder, Martha F. Gerry.
- children: Robert L. Gerry, IV and Lloyd Harriman Gerry
Former CEO of Vaalco Energy Inc., a public oil company. Vaalco's primary source of revenue is from the Etame field located offshore Gabon in West Africa. Current board members of Vaalco include former Ambassador Will Farish and Robert H. Allen.
- Vaalco Energy Inc., Chief Executive Officer (1997–present)
- Nuevo Energy, President (1990–1994)
- Plains Exploration & Production Company, Board of Directors (2004–present)
- Trustee of Texas Children's Hospital, Houston (1991–present)