Gabriel Olaseni added 15 points and 12 rebounds as the Hawkeyes (17-5, 6-3 Big Ten) won in Champaign for the first time since 1999.
Aaron White chipped in 14 points and six rebounds for Iowa, which shook off Tuesday's loss to Michigan State.
The Illini (13-9, 2-7) were led by Joseph Bertrand with 20 points. Rayvonte Rice had 13.
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