The woman was travelling west on the Warrego Highway when her car was struck by another vehicle that turned out of Gowrie Road at Gowrie Mountain.
She suffered a suspected head injury in the crash.
The Toowoomba RACQ LifeFlight Rescue helicopter received the call out at 6.20pm and flew the patient to the Princess Alexandra Hospital in a serious condition.
The sole occupant of the other car wasn’t injured.