The enormous bloating mass was discovered lying in bloody water last week in Huamual, Indonesia.
It was so huge fisherman initially thought it was a boat which had run aground, but were shocked the discover it was a huge rotting carcass.
Some speculated in was a long lost sea monsters, or a giant squid – but now scientists have identified the mystery creature.
Alexander Werth, whale biologist at Hampden-Sydney College in Virginia, said he believed the 71ft long beast was actually a baleen whale.
"There is lots of stuff in the ocean that we don't know about — but there's nothing that big that remains unknown", Werth told Live Science.
He said the corpse is just in a very advanced state of decomposition – but could not say whether it was a Blue Whale or a Bryde’s Whale.
Residents had begged the government to remove it from the water due to its overwhelming revolting stench as the corpse decomposed.
It remains unclear what caused the animal to wash up on the beach – but the whale is thought to have dead for some time.
Indonesia’s Office of Marine and Coastal Resources Management said they had taken a sample to confirm the creature’s identity.
Video from the scene showed the festering mass in the shallows while locals crowded round in the red water.
Scientists yesterday revealed Killer Whales are slaughtering Great White Sharks off the coast of South Africa – hungry for the predator’s livers.
Meanwhile, a huge shark bigger than a bus was spotted off the British coast – believed to be the biggest ever in Europe.
