Smith, 25, of Birmingham, Ala., was arrested around 4:50 p.m. ET on Thursday at a security checkpoint at Hartsfield Jackson International Airport. A .38-caliber handgun was found in his carry-on bag, said Atlanta police Sgt. Greg Lyon.
Smith was charged with carrying a weapon in an unauthorized location and was taken to the Clayton County Jail in Jonesboro -- about 20 miles south of Atlanta. He posted $3,000 bond Friday, according to court records.
Smith made his initial court appearance Friday and is scheduled for a preliminary hearing on Feb. 4, according to court documents.
Bengals spokesman Jack Brennan said franchise officials will not comment on ongoing legal matters, and a call to Smith's attorney was not immediately returned. Smith was a first-round draft pick in 2009 out of Alabama.
Jon Allen, a TSA spokesman, said Smith's loaded gun is the third firearm recovered at the airport in 2013.
"We continue to remind passengers of the importance of looking through carry-on bags to ensure there are no prohibited items inside," Allen said. He added that firearms may be packed into checked baggage.
With 100 guns being confiscated from passengers' bags in 2012, the world's busiest airport also ranked first nationally in terms of the number of weapons seized from passengers.