The shark's body was discovered around 8:30 a.m. Saturday near Goosewing Beach between Westport and Little Compton, The Boston Globe reported.
"It will probably remain a mystery," Dr. Greg Skomal, a marine biologist with the of the state Division of Marine Fisheries, said of the shark's death. "The problem is the animal was so badly (abraded) by sand and rocks that it's hard to tell if it's had any interaction with fishing gear."
Gary Severa, who was tipped off to the shark late Friday night, said standing next to the shark carcass was startling, The Boston Herald reported.
"I'm surprised the guy who first saw it was not more excited, because just standing next to it, even dead, is scary," Severa said.
Severa said he suspects the shark floated in when the tide was high Friday night.
A large number of great white sightings near Cape Cod shores this summer have prompted swimming ban at all Orleans' Atlantic Ocean beaches. The ban is expected to last through Labor Day.