She will judge alongside chef and food writer Allegra McEvedy.
Forty of the best junior bakers will compete for the title and they'll complete two bakes over 10 heats.
Nadiya said: "This time last year I was in the Bake Off tent and now I get to go back and help encourage the next generation to get their bake on."
Great British Bake Off 2015 winner Nadiya Hussain has said she is "excited" to be joining Junior Bake Off as a judge.