Fitzgerald who held the head coaching role with the Swifts until 2011 then joined the Australian Institute of Sport as head coach of netball before taking up the role as assistant coach of the Australian Diamonds netball team.
The new Magic coach was also named Netball Australia Coach of the Year in 2004 and 2006 and will have input into appointing further team management support staff in the coming weeks for the Magics.
Fitzgerald said the opportunity to take up the role with the Magics was too good to miss.
"I am excited to be beginning this new chapter in my coaching career and to have the opportunity to build on the success of such an established team as Kia Waikato Bay of Plenty Magic and assist with the developing of the future coaching and playing talent is fantastic, I can't wait to begin."
Waikato Bay of Plenty Netball Zone chairman John Wiltshire said replacing one of the most successful coaches in ANZ Championship history Noeline Taurua, was always going to be tough.
"Julie has big boots to fill, but we believe she's more than up for the challenge. In appointing Julie, we have a coach that has an outstanding background in coaching, a successful record to boot and a proven ability to work to not only develop talent but to build winning teams.