"The book of Ecclesiastes teaches us there is a time and a season for all things," Gowdy said in his statement. "There is a time to start and a time to end. There is a time to come and a time to go. This is the right time, for me, to leave politics and return to the justice system."
A spokeswoman for Gowdy's office said the congressmen would not be doing any interviews this week.
Gowdy, who is finishing his fourth term, was first elected in 2010 after a contentious battle with former Rep. Bob Inglis. He represents the 4th Congressional District, which includes Greenville and Spartanburg.
The Spartanburg High School graduate and former federal prosecutor gained national prominence as chairman of the committee that investigated the 2012 attack on a U.S. diplomatic compound in Benghazi, Libya. In 2016, Gowdy criticized then-FBI Director James Comey's decision not to prosecute Hillary Clinton over her handling of classified emails.