The Island of Lanta was known long ago as "Pulau Satak", a name of Malayan origin meaning Long Beach Island. Today's name is most probably a corrupted form of the Javanese word "lantas", that means a fish grill, which is built of wood with a square grill on top where the fishes are set in a circle. This finally gave the island the name "Koh Lantas". In 1917, the name was changed to today's "Koh Lanta" and the two main islands together with 51 smaller isles became a district of Krabi Province.

At this time Lanta island was of some importance, as the trade ships between Kantang and Phuket passed the island regularly. With the construction of road No 4 from Krabi southwards to Trang and Hatyai, goods transportation changed to the road.

In the late Eighties, the first bungalows opened up the island to tourists. Resorts like Kaw Kwang, Lanta Villa, Lanta Sea House, Relax Bay Tropicana, Dream Team and Waterfall Bay Resort date back to this time.

As the mountains in the northern part of Lanta Island and the southern tip are still covered with virgin rain forest, the Forestry Department declared the South of the island together with 15 off-shore islands and the surrounding waters the Mu Ko Lanta National Park in 1990. The 62nd national park of Thailand has a total area of 134 sqkm. Wildlife is limited to some smaller mammals, like squirrels, different snakes and more than 100 bird species.

Since 1996 the island is connected to the electric power grid of the mainland and can be reached by 2 car ferries. The number of cars on the island increased rapidly and during holidays, when locals from the neighbouring provinces visit their relatives, the narrow rough roads were no longer sufficient. Today almost all roads have an all-weather surface. In January 2001 the island received the first telephone lines from the mainland, the antennas of the different cell-phone providers followed immediately. They are now working with few exceptions everywhere on Lanta Island.

Todays population counts approximately 20 000 people and consists of 95% Muslims and 4% Buddhists, who are mainly Chinese descendants and work in the local trade, especially in Saladan and Lanta Pier. The remaining 1% are Chao'le or Seagypsies, who inhabit a small settlement south of Saladan and Sang Ga-U village on the south-eastern coast.