China saw robust growth in international passenger air transport in May as more Chinese travel overseas.

China's airliners served about 54.5 million passengers last month, up 8.7 percent year-on-year, 4.1 percentage points higher than April, data from the Civil Aviation Administration of China (CAAC) showed.

About 6 million passengers took international flights in May, up 18.7 percent from a year ago.

Passenger air transport totaled 268 million in the past five months, up 8.5 percent year-on-year, while the number of passengers taking international flights rose 16.5 percent, CAAC data showed.

Analysts attributed the robust growth of international air travel passengers partly to the booming outbound tourism market, as increasingly affluent Chinese crave experiencing exotic cultures.