The last flight carrying US personnel and equipment had departed from Shamsi airbase in Balochistan province and the facility had been "completely vacated" by the Americans, the Inter-Services Public Relations said. "The control of the base has been taken over by the (Pakistan) army," it said.
Pakistan Prime Minister Yousuf Raza Gilani told the media that the US has vacated the airbase within the time limit given to it. He said the airbase is now under the control of Pakistani forces.
Pakistan had earlier set December 11 as the deadline for the US to vacate Shamsi airbase, reportedly used by the Central Intelligence Agency-operated drones that target militants in the country's restive tribal belt.
An America flag that was previously hoisted at the airbase was lowered on Sunday, TV news channels reported.
Personnel from the Civil Aviation Authority and Frontier Corps had earlier moved into the base to oversee the immigration procedures for the Americans and to provide security. The US personnel had removed radars and other sensitive equipment from the base.
Much of the gear and at least five drones were transferred to Afghanistan. Over 70 Americans were based at Shamsi, media reports said.
Following the NATO air strike on two military border posts that killed 24 soldiers on November 26, Pakistan had asked the US to vacate Shamsi airbase in 15 days.
The United Arab Emirates had leased the airbase, located about 300 km from the Balochistan capital of Quetta, in 1992 for use by members of the country's royal family who travel to Pakistan every year for hunting expeditions. The UAE gave the US access to the facility after the 9/11 terror attacks.
Shamsi airbase was originally built to operate small aircraft and the US extended the runway so that larger military aircraft could be based there.
Numerous reports by the Pakistani and American media have said that Shamsi was used by CIA-operated drones that carried out attacks on militants in Pakistan's restive tribal belt.
Sources said the Pakistani leadership will decide whether to hand over Shamsi airbase to the UAE after its vacation by the US.