Mattison served the last four seasons as Michigan's defensive coordinator under Brady Hoke. He was also the team's linebacker coach in 2014. He previously served as the Wolverines' defensive line coach and then as defensive coordinator from 1992 to 1996.
"Michigan is a special place to me, and I am excited to be a part of Jim's staff," said Mattison. "This university and this community mean a lot to me and my family. Having the opportunity to continue coaching a group I've grown so close to is very special. I look forward to continuing my work with these young men."
Last week, the Wolverines hired D.J. Durkin as their new defensive coordinator. Durkin had been Florida's defensive coordinator since 2013.
Under Mattison, Michigan ranked among the top 20 nationally in three of the last four seasons in total defense, pass defense and scoring defense. The Wolverines held opponents to an average of 22.4 points in 2014, which was No. 28 in the FBS.
- Molly Geary