Hussain, who won 2015's Great British Bake Off, will judge alongside chef and food writer Allegra McEvedy.
CBBC's Junior Bake Off sees 40 youngsters aged nine to 12 competing for the title.
Hussain 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."
The contestants will each complete two bakes over 10 heats, including a technical bake and showstopper challenge, with four youngsters in the grand final.
The CBBC show's previous judges have included Mary Berry, Paul Hollywood, James Martin and Graham Hornigold.
Hussain, 31, has built a career since winning Bake Off which includes her first cook book, a column for The Times and a request from Buckingham Palace to make a cake for the Queen's 90th birthday. She will also present The Chronicles of Nadiya, a TV show tracing her culinary roots in Bangladesh.
She won last year's final on BBC One after baking a "big fat British wedding cake" adorned with jewels from her own wedding day as the showstopper.
It became the most-watched TV programme of the year with an average audience of 15.1 million people, according to consolidated figures, which include catch-up viewing.
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Eli Walker finished a slick Ospreys move for the opening try, before Rory Hughes' score put Glasgow 13-10 up at half-time.
Sam Davies' boot kept Ospreys in touch but Ryan Grant's controversial try restored the visitors' lead.
Ospreys levelled again with Dan Evans' incisive score and Davies missed a late chance to win the game as his drop-goal attempt sailed wide.
The hosts stay seventh in the Pro12 table, while Glasgow reclaim eighth spot from Cardiff Blues.
Buoyed by a European Champions Cup win against Racing 92 in their last outing, Glasgow made a strong start and led 6-0 thanks to two Duncan Weir penalties.
Ospreys responded first with a Davies penalty and then a smartly worked try from a line-out move, which culminated in a pop pass from centre Josh Matavesi to wing Walker, who sped over unopposed.
There was also deft handling in Glasgow's opening score, with lock Leone Nakarawa offloading brilliantly for wing Hughes to touch down in the corner.
A second Davies penalty brought Ospreys level at 13-13 early in the second half, but Glasgow soon restored their lead with a contentious try.
Referee Peter Fitzgibbon consulted television match official Jon Mason and, although there appeared to be a double movement from back row Ryan Wilson, the score was awarded as prop Grant plunged over from close range.
Ospreys equalised for the second time with 10 minutes left to set up a tense finale, with Davies' break and offload setting up full-back Evans to cross for their second try.
Davies had an opportunity to put the hosts in front three minutes later but pulled his drop-goal wide.
Ospreys: Dan Evans, Tom Grabham, Owen Watkin, Josh Matavesi, Eli Walker, Sam Davies, Brendon Leonard (capt); Nicky Smith, Sam Parry, Dmitri Arhip, Rynier Bernardo, Rory Thornton, Joe Bearman, Sam Underhill, Dan Baker
Replacements: Scott Otten, Gareth Thomas, Ma'afu Fia, Adam Beard, Olly Cracknell, Tom Habberfield, Ben John, JJ Engelbrecht
Glasgow Warriors: Peter Murchie; Lee Jones, Taqele Naiyaravoro, Sam Johnson, Rory Hughes, Duncan Weir, Grayson Hart; Ryan Grant, Pat MacArthur, Sila Puafisi, Greg Peterson, Leone Nakarawa, Rob Harley, Chris Fusaro, Ryan Wilson (capt)
Replacements: James Malcolm, Gordon Reid, D'arcy Rae, Josh Strauss, James Eddie, Ali Price, Gregor Hunter, Glenn Bryce
Referee: Peter Fitzgibbon (IRFU)
Assistant referees: Leighton Hodges, Wayne Davies (both WRU)
Citing commissioner: Gwyn Bowden (WRU)
TMO: Jon Mason (WRU)
Former Bake Off winner Nadiya Hussain has said she is "excited" to be joining the show's junior version as a judge.
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Ospreys and Glasgow shared four tries in an entertaining draw in the Pro12.