The crash, involving a Cessna aircraft, happened at Loanends, just over two miles from Belfast International.
The Air Ambulance is at the scene of the crash.
Emergency services – fire, police and ambulance crews – are also at the scene.
It is understood the pilot and passenger have been pronounced dead at the crash site.
Initial reports said the plane heading toward Belfast International Airport.
But that has been denied by the airport which said in a statement that the plane was not operating out of it, or heading toward it to land.
A spokeswoman said: “It crashed in the vicinity of Loanends, two-three miles from the airport.”
The Fire and Rescue Service said: “NIFRS is currently attending the scene of a light aircraft on fire near Nutts Corner, Crumlin.
“The call was received at 12.22 pm today and three Fire Appliances from Antrim, Crumlin and Glengormley Stations are at the scene.
“Ambulance and PSNI are also at the scene. The incident is ongoing.”
The Northern Ireland Ambulance Service said paramedics and three ambulance crews plus two officers and an air ambulance have been sent to the scene.
The PSNI said: “Police and other emergency services are currently in attendance at the scene of a light aircraft crash in the vicinity of Nutts Corner, Crumlin.
“There are no further details at this stage.”