It is believed that the macaque headed out of a nearby forest in search of food, touched an electric cable and was killed.
Pichet Konklong, a local resident, said he noticed the animal lying still on the road at about 9am and decided to alert authorities.
“I stopped my motorcycle to check what I could do. But it was already dead,” he said.
Officials said the animal was just a few years old.
Electrocution burns were visible on its right cheek and right leg.
Authorities have received several reports about electrocuted macaques in recent years.