Midway also canceled some 500 flights on Saturday.
"Due to overnight snow and strong winds expected throughout the day, airlines at O'Hare International Airport have canceled nearly 470 flights," the airport management tweeted.
A lakeshore flood warning was also issued, as waves in Lake Michigan could reach up to 3 meters.
O'Hare recorded more than 10 cm of snow in the early morning and Midway, the other international airport in Chicago, had 8 cm.
CHICAGO, Jan. 19 (Xinhua) -- More than 5000 flights were canceled at Chicago's two international airports on Saturday as a powerful winter storm hit central and northeastern United States.
He asked residents to remain indoors if possible and take the weather warnings seriously.
"Chicago is no stranger to winter weather and the city is prepared to work tirelessly to make sure residents are safe," Chicago Mayor Rahm Emanuel told a news conference on Friday.
Other flights to and from the airport were disrupted by an average delay of 18 minutes, according to Flightradar 24.
Weather forecasters said that snow was predicted to fall up to 2.5 cm per hour on the city, with high-speed gusts. Additional lake-effect snow will fall from midday Saturday into Sunday evening.
Authorities said both airports were fully stocked with supplies, including over 6,000 tons of salt and over 4500,000 gallons of deicer fluid.