What is best way to travel by bus from Shanghai downtown to Hangzhou airport?

Hi, James. There are no direct bus to the airport. But, you may take a long-distance bus to Hangzhou from the General Bus Station at no. 1666 on Zhongxing Road for CNY 68. The bus is available from 7:10 to 17:20, and the duration is about 2.5 hours. Then, you may take a taxi to the airport for about CNY 100, and the duration is about 45 minutes.

Actually, you are advised to take a high speed train from Hongqiao Railway Station to Hangzhou Railway Station, or Hangzhou East Railway Station. The train is available from 6:14 to 21:31, and the duration is about 1 hours. The hard seat costs CNY 73 or 77. 5; the hard sleeper costs CNY 117 or 123.5; the soft sleeper costs CNY 219.5 or 233.5. Upon arrival, take an airport shuttle bus to the airport. The duration is about 30 minutes, and the fare is CNY 20. :)