Richmond County Deputy Coroner Kenneth Boose said Kathryn Gilmer, 41, of Augusta, died after being ejected from the vehicle.
According to a news release from the sheriff's office, deputies were called to the 2200 block of Morningside Drive about 1 a.m.
Police believe the 1999 Isuzu Trooper was traveling east but was unable to maintain its lane and struck an oak tree.
The driver, Michael Lindsey Johnston, 43, of Helmsdale Lane in Augusta, was taken to Georgia Regents Medical Center with serious injuries and burns.
Police said that speed was a contributing factor and that alcohol possibly was involved.
An accident reconstruction team is investigating.