The 23-year-old small forward earned promotion following some impressive form in the VFL, where he has slotted 27 goals in 12 matches.
The No. 29 pick in last year's NAB AFL Rookie Draft, Dell’Olio now has the chance to add to his 2012 tally of eight AFL appearances and nine goals.
He went goalless just twice in his debut season.
"Cory has showed consistent form this season at VFL level and we have been really pleased with some of his recent performances," Essendon football operations manager Steve Alessio told the club website.
"He has experienced AFL football before and hopefully he can be an important forward line option for us heading into the closing stages of the season."
