The TSA said the man had the gun in his carry-on bag last weekend. The 9-mm gun, loaded with eight rounds of ammunition, was found during an X-ray screening on Saturday morning.
It was the fourth gun found at the airport during the screening process this year.
Officials say firearms are allowed in checked bags, but they must be unloaded, packed in a locked container and announced to the airline at check-in.
It is unclear what charges, if any, the man faces.
The Associated Press contributed to this report.