Dave Joyner told the Associated Press he enjoyed the honor and privilege of working for his alma mater for nearly three years as athletic director following a national scandal and the death of head coach Joe Paterno.
"It was a privilege for sad reasons, but it was a privilege," he told the AP.
Joyner gave no specifics about why he made the decision to leave.
Joyner was appointed interim AD in November 2011 after Tim Curley was placed on administrative leave for his alleged role in the Sandusky scandal.
Joyner said he will resign Aug 1.
Sandusky was sentenced to 30 to 60 years in prison after being was found guilty on 45 charges related to years of child molestation accusations.
Penn State will form a search committee and work with a consulting firm in the search for its next athletic director, according to the AP.
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