The Qatar Airways plane was escorted in to land by the Royal Air Force (RAF) following information received by the pilot.
"Flight QR23 from Doha to Manchester, an Airbus A330-300, landed safely at Manchester Airport ahead of its scheduled arrival time of 13:15. There were 269 passengers and 13 Qatar Airways crew on board," Qatar Airways said in a statement.
"The crew had received a threat about a possible device on board and Qatar Airways immediately took all the necessary precautions to alert British authorities," the airline said.
"The crew is now fully assisting police at the airport with their inquiries. The safety and well-being of our passengers and crew is our top priority. As this is a matter of a police investigation, we cannot comment further at this time," it said.
Greater Manchester Police said officers were treating it as a "full emergency" as they did not know "how genuine this threat is". A passenger was taken off the plane by officers at Manchester Airport before the others could disembark. All flights in and out of the airport were suspended for about 25 minutes.
"It's now business as usual (at Manchester Airport) due to swift partnership response. Police are still dealing with the matter as an isolated incident," the police statement said.
The airliner was escorted by a Typhoon from RAF Coningsby in Lincolnshire.
Earlier, chief Supt John O'Hare said the safety of those on board was "paramount".
Chief Superintendent O'Hare said, "An incoming plane has been escorted into the airport by the Royal Air Force as a result of information received by the pilot about a possible device on board.
"We don't know how genuine this threat is but it is absolutely vital we deal with the situation as a full emergency.
"As a result people will see the police and other agencies at the airport and on the airfield. At this time I would urge them not to be alarmed.
"Our response will be as comprehensive as it is proportionate, with the safety of those on board and in and around the airport our paramount concern."