Sonnen is from West Linn, Oregon and began wrestling from a young age. After graduating from West Linn High School where he was a state runner-up, Sonnen attended Brigham Young University before transferring to the University of Oregon when BYU began considering cutting their wrestling program. At Oregon, Sonnen earned All-American honors, was a two-time PAC 10 runner-up, was a silver medalist at the 2000 Greco-Roman World University Championships, and was a two-time Dave Schultz Memorial Institutional Greco-Roman winner.