Jefferson City resident Kelli C. Smith, 22, was seriously injured when her car struck another car early Saturday morning, killing the passenger of that car.
The Missouri Highway Patrol has not yet named the passenger of the other vehicle.
The patrol said the wreck occurred about 3:30 a.m. on I-70 at the 170-mile marker in Montgomery County.
Smith's vehicle was traveling westbound in the eastbound lanes when it struck the other vehicle head-on, causing that vehicle to catch fire.
Smith was flown by helicopter to University Hospital in Columbia, where she remained in serious condition on Sunday.
Smith was wearing a seat belt. It is not known whether the other driver, who was pronounced dead at 4:55 a.m., was wearing one.
The patrol said the investigation is ongoing.
This marks the sixth fatality for the patrol's Troop F in 2012 and the third this month.