The shooting occurred at about 3 p.m. near Howard and Custer, Evanston police said.
Police said all three victims are documented gang members and that the shooting appears to have been gang related. Police said both the victims and the shooter or shooters were in two separate cars when one car opened fire on a red SUV. It is not clear if the victims fired back at the shooters.
Police said all three victims were taken to St. Francis Hospital. Two victims are in good condition, while the third victim is in critical condition and in surgery as of 4:45 p.m.
Police said all three victims are men older than 18 and younger than 25.
Police are still trying to determine exactly what led up to the shooting.