Rig worker Vitisak Payalaw documented the rescue and posted pictures to social media.
He said it was the calm seas that allowed workers to spot the dog, saying that if there had been waves, they wouldn’t have noticed him.
Payalaw said the canine was covered in salt but seemed otherwise fine.
Workers speculated the dog, which they named Boon Rod or Survivor, probably fell off a fishing boat and that it was a miracle he even survived.
They contacted a Thailand animal rescue organization, which sent a boat out Monday to pick Survivor up and take him ashore for a medical assessment and eventual adoption.
Payalaw said if the dog was still with the group when he returns to shore from the oil rig, he intends to adopt him.