Joyner took over as the school's acting athletic director on Nov. 17, 2011, following the Jerry Sandusky child-sex abuse scandal and was officially given the job two years later.
The school was hit with several penalties because of the scandal, including being stripped of scholarships, fined $60 million and banned from playing in any postseason game until 2016.
In that time, Bill O'Brien took over as football coach after Joe Paterno was fired. O'Brien has since left and is now the head coach of the NFL's Houston Texans. Former Vanderbilt coach James Franklin took over the job earlier this year.
"It has been an honor and privilege to serve Penn State," Joyner said. "Our student athletes, coaches, staff and the University community were a daily source of inspiration for me. The spirit of Penn State is strong, and the department's commitment to integrity, as well as academic and athletic excellence is stronger than ever.".JOHNSON: James Franklin and Penn State laying a foundation for the future with 2015 recruiting