Ko Chang (เกาะช้าง) is in Trat Province, in Eastern Thailand, about 330 kilometers from Bangkok. It is Thailand's second largest island, and the biggest in Ko Chang National Park. With about 5000 permanent residents the island is not heavily populated, but tourism (and development) has increased dramatically over the last few years.

The largest island in the Ko Chang Marine Park archipelago, Ko Chang was named for the elephant shape of its headland, although elephants are not indigenous to the island.

Ko Chang (เกาะช้าง) previously an unsettled island, is now important as a harbour for ships to escape from the monsoon, and dietary or fresh water resources, especially at Ao Salak Phet or Ao Salat which is well known to pirates, Hai Lam Chinese and Vietnamese. At present, there are 8 villages on the island.

Ko Chang is being heavily developed. It seems like the government is trying to "develop" it from a backpackers' paradise to a top-level destination. Construction work is going on throughout the island, with basic huts torn down to make way for fancy resorts.