The single-vehicle accident occurred at approximately 8:30 a.m. on Bloomingdale Road where it intersects with Timbertree Road, Sullivan County Sheriff's Office spokeswoman Leslie Earhart said.
The woman killed in the wreck has been identified as Sharon Livesay, 68, Bloomingdale Road.
According to the SCSO, Livesay was driving on Bloomingdale Road when she lost control of the vehicle, causing it to go off the right side of the roadway.
The car then reportedly crossed back over the both lanes before hitting an embankment and overturning.
The driver was pronounced dead at the scene, Earhart said.
Witness told authorities that Livesay did not appear to be speeding just prior to the accident.
Members of the Sullivan County Sheriff's Office F.I.R.S.T. (Fatal Incident Reconstruction Support Team) division responded to the wreck.
A sheriff's office spokeswoman said investigators with the team are still trying to determine what caused the fatal accident.
Authorities said Livesay was not wearing a seatbelt with the incident occurred.
The story has been updated to identify the victim.