Airport officials told ABC11 that a smoke indicator light on JetBlue flight 1117, an Airbus 320, went off in the cockpit for a compartment underneath the aircraft.
The pilot declared an "Alert 2" emergency and landed at RDU at 7:13 p.m.
After landing, fire crews checked the plane.
Officials said there was no immediate danger to the 138 passengers and crew members on board.
The plane resumed its flight at 9:35 p.m. after being checked by mechanics.