Ko Samui or Koh Samui, is an island off the east coast of the Kra Isthmus, Thailand. Geographically in the Chumphon Archipelago, it is part of Surat Thani Province, though as of 2012, Ko Samui was granted Municipality status and thus is now locally self-governing. Ko Samui is Thailand's second-largest island after Phuket, with an area of 228.7 km2, a population of over 63,000 and a hotel occupancy rate of 73 percent as the number of visitors increases. Abundant tourist resources, sandy beaches, coral reefs, and coconut trees are present on the island.

Koh Samui (Samui Island) is a cosmopolitan melting pot, attracting budget travellers staying for a month or two in simple beachside bungalows, to the wealthiest holidaymakers dropping in for a weekend at one of the many luxury resort or villa on the many white sand beaches of Koh Samui. From the hustle and bustle of Chaweng Beach to the lively yet relaxed atmosphere of Lamai Beach to the timeless feel of Bophut's Fisherman's Village to the tropical beach paradise of Maenam, Koh Samui is unique among Thailand's islands in maintaining a broad appeal for everyone.