Newton has been signed as a replacement player for the injured Meg Lanning, with the Scorchers seeking and receiving approval from the League Technical Committee.
Newton started her career as a right-arm medium pacer, playing for Wellington Blaze in the State League.
The 22-year-old made her debut for New Zealand in a T20I game against Sri Lanka and recorded the second best bowling figures for a New Zealand woman when she picked up 5-31 last year against Pakistan.
“I’m excited and nervous about getting amongst the team,” Newton said.
“I haven’t had much experience playing in Australia so I am looking forward to learning as much as I can.
“I was attracted to playing for the Scorchers because I definitely want to don some orange, but I also have some family over here.
“The Scorchers have had a quite a bit of success in the WBBL, so it will be great to get amongst their environment and see how they run things.”