The event took place Tuesday night at the Ritz-Carlton hotel in Chicago. Among the guests at the gala were Chicago Mayor Richard M. Daley, Illinois Gov. Rod Blagojevich and Chicago Roman Catholic Cardinal Francis George, the Chicago Sun-Times reported.
The award is bestowed upon "those singular individuals who accept the responsibilities imposed by history and demanded by conscience."
Tutu, 76, was recognized for his activism and work in helping to end apartheid in South Africa.
"What if he'd settled on medicine or on teaching rather than his third career choice, the ministry?" the Sun-Times quoted Winfrey as saying in her introduction. "Without Archbishop Tutu, how would South Africa be different? How would the world be different?"
"There is a great deal of evil in the world and we ought not pretend that isn't the case," Tutu said. "And yet you discover there's a great deal of good as well."