The MD-83 Saudi plane, carrying 72 passengers and crew members, was en route from the northern Saudi city of Tabuk to Quetta in Pakistan when the pilot diverted the jet to Karachi over concerns about the wheels.
"The aircraft made an emergency belly landing. All 72 passengers and crew remained safe," Pervez George, spokesman for Pakistan's Civil Aviation Authority, told AFP.
George declined to give further details when asked about damage sustained by the plane in the landing.
"The concerned officers are examining the aircraft," he said.