Robert Jones "Rob" Portman (born December 19, 1955) is an American lawyer and elected official who has served in two federal cabinet positions and as a member of Congress. Most recently, he was Director of the Office of Management and Budget (OMB). Prior to this appointment, Portman was the United States Trade Representative, a post carrying the rank of Ambassador. From 1993 to 2005, he was a Republican member of the U.S. House of Representatives from Ohio, representing that state's 2nd congressional district (map), which stretched along the Ohio River from the Hamilton County suburbs of Cincinnati east to Scioto County.

He was confirmed by the Senate as U.S. Trade Representative on April 29, 2005, and privately sworn into his new office that day. On April 18, 2006, President Bush nominated him to fill the role of Budget Director; its former director, Joshua Bolten, was promoted to White House Chief of Staff.

On January 14, 2009, Portman officially announced his candidacy for the open Senate seat being vacated by retiring Senator George Voinovich.