Christopher John O'Leary (born November 7, 1991) is an American professional football coach who is the defensive coordinator for the Los Angeles Chargers of the National Football League (NFL). He previously served as the defensive coordinator and safeties coach at Western Michigan University in 2025. O'Leary played college football for the Indiana State Sycamores. He previously served as an assistant coach for the Georgia State Panthers, Florida Tech Panthers, and Notre Dame Fighting Irish.