The A8 has been closed overnight in both directions between the airport junction and the Newbridge roundabout following reports of shots being fired last night around 9.30pm.
Motorists are asked to avoid the area as long delays are expected, especially during rush hour, and the road is expected to remain closed until at least mid-morning.
The only way to access the airport is from the east. Drivers from the west should continue along the the M8 to the Edinburgh City Bypass (A720) and head towards the Gogar roundabout from where they can travel down the A8 from the east. Passengers are asked to allow plenty of time.
A spokesman for Police Scotland said there were no reports of injuries.
He said: “Police Scotland is carrying out inquiries following reports of shots being fired in the Newbridge area last night around 9.30pm.
“No one was injured in the incident; however, the A8 between the Newbridge Roundabout and Edinburgh Airport is closed in both directions while a detailed search of the area is carried out.
“Police Scotland apologises for the disruption to traffic, which will result from this road closure and urges motorists to seek alternative routes for their morning journeys. The search will take some hours to complete and it is hoped the road will re-open in mid-morning.
“Anyone with any information about this incident is asked to call Police Scotland on 101 or the charity Crimestoppers on 0800 555 111.”