Pilot John Pedersen said he was flying solo over the city at around 6 a.m. local time when his two-seater plane began vigorously shaking.
He landed on Lake Shore Drive, gliding over traffic that had stopped at a red light at Buckingham Fountain, the Chicago Tribune reported.
"There's no way I could have got it to Midway or O'Hare," Pedersen said.
The pilot walked away from the crash unscathed, but shaken, WLS-TV, Chicago, reported. There were no injuries on the ground.
"It's a blessing," Pedersen said.
Investigators said the accident was caused by a mechanical issue with the tail control of the aircraft.