The 39-year-old, who forged a successful playing career in the Netherlands and Austria, resigned his post to focus on pursuits outside of football.
 
Didulica is the first to leave the coaching ranks since the arrival of new head coach Warren Joyce last month.
 
His exit follows a shake-up in the goalkeeping roster with former Denmark International Thomas Sorensen released at the end of last season and ex Red's skipper Eugene Galkekovic picked up.
 
The Geelong-born Didulica was appointed by the club’s coaching roster in 2011, working throughout the past six A-League seasons.
 
In addition to working with the first-team goalkeepers, the former Ajax and Austria Vienna shot stopper has helped develop the outfit's rising talent, including James Delianov and Yaren Sozer who both recently made their Young Socceroos debuts.

In an official statement the club said it "thanks Joey for his contribution during his time at Melbourne City FC, and wishes him all the best for the future".