All Blacks call up Crusaders flyhalf
Star flyhalf Beauden Barrett suffered a head knock in New Zealand's win over South Africa earlier this month, opening the way for Mo'unga's inclusion.
The world champions also lost wing Nehe Milner-Skudder to a season-ending shoulder injury in the same match.
They said Mo'unga, 23, was coming in as "temporary cover" for the Wallabies match. He is likely to be third-choice flyhalf after Lima Sopoaga and Damian McKenzie.
Lock Patrick Tuipulotu will remain with the squad as a replacement for Luke Romano, who is having time off following the birth of his baby son.
The Wallabies have so far failed in their quest to beat the All Blacks this year after two defeats in Sydney and Dunedin in August.
New Zealand's starting XV will be named on Thursday.
New Zealand squad:
Forwards: Wyatt Crockett, Kane Hames, Nepo Laulala, Jeff Toomaga-Allen, Ofa Tu’ungafasi, Dane Coles, Nathan Harris, Codie Taylor, Scott Barrett, Patrick Tuipulotu, Samuel Whitelock, Sam Cane, Vaea Fifita, Jerome Kaino, Kieran Read, Ardie Savea, Liam Squire and Matt Todd.
Backs: Tawera Kerr-Barlow, TJ Perenara, Aaron Smith, Beauden Barrett, Richie Mo’unga, Lima Sopoaga, Ryan Crotty, Ngani Laumape, Anton Lienert-Brown, Sonny Bill Williams, Rieko Ioane, Waisake Naholo, David Havili and Damian McKenzie.
Agence France-Presse