The 19-year-old was criticised by his manager Massimiliano Allegri and team-mate Leonardo Bonucci for the way he celebrated at the end of the Serie A match during which he was subjected to persistent racial abuse.
Kean, who was also subjected to monkey chants stood next to the post, his arms spread wide, after netting in the 2-0 win and Chiellini has fully backed the actions of the teenager.
"Moise is an asset to Italian football, a golden boy who is doing his best and he doesn’t have to pretend to be something he’s not," he told Juventus TV.
"I don’t really remember what happened while I was on the pitch, but I’ve seen the pictures of Moise and he didn’t do anything wrong.
"The only thing he got wrong yesterday was the dive, which I’m sure he won’t repeat, but he’s here to learn. He’s a very positive person and certainly didn’t deserve the insults he received."
Teammate Blaise Matudi also took to social media to pledge support to the Italy international.
— Blaise Matuidi (@MATUIDIBlaise) April 2, 2019