Ko Chang (Thai: เกาะช้าง, also Koh Chang) is an amphoe (district) in Trat Province, Thailand. It is on the Gulf of Thailand's eastern seaboard, 310 km from Bangkok, near the border with Cambodia.
It is the country's third largest island, after Phuket and Ko Samui, and the largest island in the Mu Ko Chang National Park archipelago.
The name means "Elephant Island", and comes from its elephant-shaped headland. Despite the presence of elephants on the island, they are not indigenous. At present, there are nine villages on the island.