The Borphud police station on the island-district was alerted to the discovery at 5.30pm.
A villager spotted the bones among trees about 200 metres from the side of Ban Lamai-Ban Mae Nam road. The bones were still intact and were under clothes.
Police checked the scene and found a cutter, a red mobile phone sleeve and a pair of sandals near the remains.
There were no identification documents at the scene and police could not tell whether the remains belonged to a man or a woman, or a Thai or migrant worker.
The remains were sent to the Samui Hospital for further examination.