How far is Hainan island from Hong Kong

Hi, Nelani. It is hard to tell the distance, since the two islands are seperated by the sea.
If you use the transportation on land, you need to reach Guangzhou first and then to Haikou, in this way, the distance is around 1000km.
If you use flight, it may take you around one hour from HK to Haikou.

Hope it helps you ~