Susan Combs (born February 26, 1945) is an American politician, having served elected office in Texas and as the assistant secretary of policy, management and budget at the U.S. Department of the Interior under President Donald Trump.

A Republican, Combs served from 2007 to 2015 as the Texas Comptroller of Public Accounts. Prior to her tenure as comptroller, Combs had served two terms as commissioner of the Texas Department of Agriculture from 1999 to 2007, taking the reins as the first woman elected to that office in 1998. Combs also served two terms in the Texas House of Representatives.

Combs was born in San Antonio. She grew up in a ranching family in West Texas. She runs a cow-calf operation on her family's ranch in Brewster County; the ranch has been in her family since the turn of the 20th century. She lives in Austin with her husband, Joe W. Duran, a computer scientist. She is the mother of three sons. Combs graduated from Vassar College in Poughkeepsie, New York, majoring in French and religion. She worked in international advertising in New York City, in the financial markets on Wall Street, and for the U.S. government before returning to Texas to obtain credentials from the University of Texas Law School at Austin. After graduation from law school, she served as an assistant district attorney in Dallas, Texas.

Combs' first electoral outing was for the 47th legislative district, in Travis County. She won the Republican runoff election by seven votes over intraparty challenger Bill Welch. Combs polled 2,279 votes (50.07 percent) to Welch's 2,272 (49.92 percent). The two had led a five-candidate field in the primary. In the general election, Combs handily defeated the Democrat Jimmy Day, 45,355 (65.4 percent) to 23,987 (34.6 percent). Combs served two terms in the Texas House of Representatives from 1993 and 1996, resigning midway in her second term to join the staff of U.S. Senator Kay Bailey Hutchison as the lawmaker's state director. She was succeeded by fellow Republican Patty Keel of Austin.

Combs served as the Texas agriculture commissioner from 1999 to 2007, being the first woman to serve in the position. She succeeded Rick Perry as commissioner, who was instead elected as lieutenant governor.

As agriculture commissioner, Combs worked with the Environmental Defense Fund to protect the golden-cheeked warbler. In partnership with Combs and the Texas Department of Agriculture and a coalition of other organizations, Environmental Defense Fund coordinated the development of a market-based credit exchange. It allowed Fort Hood to quickly obtain offsets from nearby landowners to counteract losses from live-fire training activities and troop movement through core habitat areas.

Combs was elected as Texas comptroller of public accounts to succeed Carole Strayhorn. Combs served as comptroller from 2007 to 2015. In 2010, Combs was unopposed for a second term as comptroller in the Republican primary, and she faced no Democratic opponent in the November 2 general election. Unsuccessful nominees of the Green and Libertarian parties did seek the position. Combs did not seek reelection to a third term as comptroller or any other statewide office in the 2014 elections.

In 2015, Combs endorsed Carly Fiorina for president.