The college identified the student as Ethan Roser, a 19-year-old transfer student from Cincinnati, Ohio.
At about 4:15 p.m., Roser was volunteering during the competition when he was struck by a hammer during the hammer throw event, the college said in a statement.
Roser was transported to Good Samaritan Hospital in Downers Grove where he was pronounced dead.
"We are deeply grieved, but, because of our faith in Christ, not without hope," said Wheaton College President Philip Ryken. "We ask people to pray for Ethan's family, his friends, and our campus community."
Roser was a member of the soccer team. A community prayer event was scheduled for 9 p.m. Saturday at Pierce Chapel.