The Italian giants managed to sign him from Real Madrid for €105 million last summer.
That might seem like quite a lot of money for a player who was 33 at the time, but he's gone on to prove that he was worth every penny.
Ronaldo has scored 32 times in 51 appearances since joining.
He also helped his side to the Serie A title and a Supercoppa Italiana triumph.
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But it's not just on the field where Ronaldo has contributed.
His presence has also helped Juventus' brand dramatically.
According to Gazzetta dello Sport, per the Daily Mail, Ronaldo's presence allowed the Italian side to earn €58million extra revenue in the 2018/19 season.
His presence also helped Juventus sell 1.3 million shirts; the 10th most in the world during the 2018/19 financial year.
The club's fanbase is also believed to have grown by 38 million since Ronaldo joined the club.
Juventus now have 423 million supporters across the globe, meaning they have risen from eleventh to eighth in the world rankings.
Juventus' social media followers have also increased dramatically.
Across Facebook, Instagram, Twitter and YouTube, Juventus has gone from 50.4 million followers in June 2018 to 84.8 million.
That makes the Italian giants the fourth most followed team on social media, behind Real Madrid, Barcelona and Manchester United.
And Ronaldo' signing has also helped in contract renewal negotiations with primary sponsors, such as shirt sponsor Jeep.
The car company has agreed a new deal which will see Juventus triple the money they are generating now from the agreement.
It appears that Juventus have a lot to thank Ronaldo for. The €105 million that Juventus paid for Ronaldo now seems like a massive bargain.News Now - Sport News