Hong Kong International Airport reported its biggest fall in passenger numbers in more than a decade in November, official data released on Sunday showed.
The airport handled just over five million passengers, down 16.2% from a year earlier, Airport Authority Hong Kong said in a statement.
That was the largest fall since June 2009, when the figure fell by 18.7%, data on the Civil Aviation Department's website showed.
There were falls of more than 12% in the three previous months, the Civil Aviation Department data showed.
Hong Kong has been gripped by sometimes violent protests since June. Demonstrators halted operations at the airport for several days in August.
A spokeswoman at the Airport Authority said it had nothing to add to the publicly available data.