Jenkins was recruited to the Bombers in the 2010 Rookie Draft selection at pick 12 and is yet to make his senior debut.
General manager of football operations Paul Hamilton thanked the departing ruckman for his contribution to the Club.
“Josh will leave the Club with our best wishes as he endeavours to explore senior level opportunities with Adelaide,” Hamilton said.
“We are pleased that we now have a second round selection at 31 and we wish Josh all the best for his future.”
Essendon’s first three picks in the upcoming AFL National Draft now stand at 19, 31 and 59.