Police said it happened in the Cragin neighborhood's 2300 block of North Cicero Avenue just before 12:45 a.m.
A man was driving a gas-powered scooter with a passenger, another man, northbound when they collided with the side of gray sedan, which was traveling westbound, police said.
Police said both men on the scooter suffered trauma to their bodies and were transported to Stroger Hospital in critical condition. The man who was driving the sedan was not injured.
No further injuries were reported and citations are pending, police said.