Forest and fire personnel recovered the carcass of the 35-year-old tusker from the well on the outskirts of Gada Humma village, about 50 km from here under Khallikote forest range.
"The tusker was suspected to have fallen into the well while passing through the area on Friday night. Since the well is very deep and full of water, the elephant could not come out and ultimately died," Divisional Forest Officer (DFO) Berhampur S S Mishra said.
Two tusks measuring around 44 cm and 46 cm were taken out from the carcass after the postmortem, DFO said.
The number of elephant deaths reported from the Ganjam district in the past 30 days rose to eight.
The elephant was part of a herd, five of which- three females, a tusker, a calf and a foetus - were mowed down after being hit by a train on December 29 at Subalaya, forest officials said.
Another herd comprising around 11 elephants was also roaming in the area, they said.