The carcass was discovered on March 22 in waters near Dinh Thay Thim Beach, Tan Hai Commune, according to local residents.
Observers said the fish measured close to four metres in length, with a flattened, silver body and a long dorsal fin running along its length. It appeared largely intact and was floating near the shoreline when spotted.
The oarfish is typically found in deep ocean waters and is rarely seen along the coast in this area.
The oarfish is brought ashore by fishermen on March 22 (Photo: Tran Nguyen).
News of the unusual sighting quickly spread, attracting locals and tourists eager to see the specimen. Some speculated that changes in ocean currents or water temperature may have caused the fish to drift closer to shore.
Authorities in Tan Hai Commune said they were verifying the incident and gathering further information.