Transportation between Hong Kong & Guangzhou international airport?

Take a bus to Dongfang Hotel from Hong Kong Metropark Hotel Mongkok, Marco Polo Hotel Tsim Sha Tsui, Kwun Tong APM Station, or Shun Tak Centre Sheung Wan. The buses are available from 7:00 to 22:45. The frequency is about 15 to 30 minutes. The trip takes about 3 to 4 hours. The fare is HKD100. You can book the bus ticket at the official website of cts.

Upon arrival, take shuttle bus line 5 to the airport. :)