I need to go to zhangjiajie by train. Which station i should go from huanghua Airport?

You need to go to Changsha Railway station. From the airport, you can take shuttle bus line of railway station directly to it. The bus departs from 7:30 to 23:59 with around 75 minutes on the way.

thanks for the information. How about go to zhangjiajie by bus? Where should i go from the airport?

Follow the guide in the airport, you can go to shuttle bus station. If you want to take bus to Zhangjiajie, you still need to go to Changshang railway station first. Then you can take bus from nearby Changzhutan Coach station to Zhangjiajie. The bus departs from 7:30 to 19:00 with CNY120 and interval of 1 hour.