Originally, area of Koh Chang was part of Laem Ngop District, Trat Province. Later, the government has divided the administrative area to Koh Chang District. According to the announcement of the Ministry of Interior on March 31, 1994. On April 30, it became a sub-district with effect to main district on September 8, 1994

Originally, Koh Chang was an island without settlements village, there is only important as a source of food supplies. Especially in the area of Salak Phet, there are the pier for boats to escape the monsoon wind only. Currently on Koh Chang, there are about 9 villages.

Koh Chang is the largest island in the Gulf of Thailand and the second largest island of Thailand after Phuket. Koh Chang has the covers an area of approximately around 429 square kilometers, Koh Chang is largest than 50 islands around, all of small island called Koh Chang National Park.

The area on the island can be divided into two main categories: flat land and complex mountains and evergreen forests.

Koh Chang is currently one of the most important tourist destinations in the eastern region. Each year, there are many tourists who want to experience the abundance of Koh Chang. This information is guaranteed by the increasing number of tourists traveling every year on Koh Chang.

Koh Chang west coast or right of Koh Chang.
For this side, it will be a zone for full tourism, with many hotels, restaurants, famous entertainment venues. Popular beaches include White Sand Beach, Klong Prao Beach and Kai Bae Beach. If anyone is addicted to the nightlife, souvenirs, come to this side.

Koh Chang east coast or left of Koh Chang.
For this side, it is suitable for those who like peace and quiet. There are no beaches that can be played on this side. There will be various waterfalls, local fishermen's way of life and there are many community attractions. The highlight activity is taking the Gondola at Salad Petch to Salad Kok. This side is for Slow life lover, suitable for people who want to relax comfortably.