The 85-year-old former senator and astronaut suffered a fractured sternum and says his chest is "very sore."
The Glenns were returning from a political fund-raiser at a suburban Columbus country club when Glenn tried to turn onto a highway ramp and hit another car.
The driver of the second car wasn't hurt.
Police cited Glenn for failure to yield.
Doctors say neither Glenn nor his 86-year-old wife was seriously hurt.
But Glenn says there's nothing minor about the pain in his chest.