Fuller, who played eight caps for the Silver Ferns from 1994 to 1996, has been in the part-time role since 2018 under coach Noeline Taurua, who was also recently reappointed as head coach.
"I am excited about working with the squad," Fuller said.
"We have some high-quality athletes who are keen to take the game to another level of dynamic game play.
"It’s challenging, fun and always a privilege to help our Silver Ferns explore what they can do with the game."
Under Taurua and Fuller, the Silver Ferns won the Netball World Cup in 2019, finished fourth in 2023, and won bronze at the 2022 Commonwealth Games.
A high calibre of coaches applied for the assistant coach role, but Fuller’s vision for the team’s future and alignment with Netball New Zealand’s high performance objectives made her successful.
Northern Stars departing coach Kiri Wills, who is heading to the Queensland Firebirds next season, was among those to throw her hat in the ring.
"We were fortunate to have a strong pool of candidates for the Silver Ferns assistant coach position," Netball New Zealand head of high performance Stephen Hotter said.
"Debbie stood out among them with her exceptional coaching credentials and her thorough understanding of what it takes to succeed at the highest levels of netball."
Netball New Zealand will also appoint a specialist coach with the appointment to be confirmed this month.
