David Marshall, 43, of Grayson died Tuesday night in a West Virginia hospital, more than a week after an all-terrain vehicle accident on Ky. 409 in Elliott County.
Marshall was driving a 2008 Yamaha Grizzly ATV north on Ky. 409 on June 12 when he lost control, according to a state police release.
He was thrown from the ATV and struck his head on the road. Marshall was not wearing a helmet.
He was flown to Saint Mary's Regional Medical Center in West Virginia, where he died Tuesday.