Kunming Changshui International Airport is yet to handle the departure of 283 flights that had been grounded due to misty weather since yesterday, operators said.
The officials reported nearly 10,000 passengers present at the airport during midnight. Operators said they were making "all-out efforts" to maintain order and to arrange accommodation for the stranded.
Massive flight delays began to hit the airport on Thursday after thick fog dropped the visibility to 300 to 800 metres.
All delayed flights are expected to take off later today, state-run Xinhua new agency reported.