The 25-year-old has moved to the East London club initially on a season-long loan deal which contains an option to make the move permanent at the end of the spell.
West Ham had been seeking a quality striker to support Andy Carroll all summer and after failing to secure the signing of Alexandre Lacazette, Zaza's arrival will have been a relief.
The striker had found his opportunities limited at Juventus, making only 19 appearances behind Mario Mandzukic, Paolo Dybala, Alvaro Morata (now at Real Madrid) and most recently Gonzalo Higuain.
"OFFICIAL - @SimoneZaza will play at @WestHamUtd this season #ThanksSimo"
Dybala was quick to pay tribute to his friend and teammate upon news of his departure to the Premier League.
"Good luck for this new adventure @SimoneZaza! We'll miss you my friend!"
Many Juventus fans also appreciated Zaza's performances in his few appearances for the club, which included five goals.
"Goodbye #zaza, sorry to lose a fighter like you. Thank you for the last year with Juve. Good luck. #Juve #simonezaza #westham"
"I will miss you so much @SimoneZaza. Good luck at West Ham. You will remain in our striped hearts."
I'll miss you! Good luck for your new adventure at West Ham...Show them what you're made of!"
Zaza's reply to the tweet above reads: "THANK YOU. And I'm speaking from my heart." One of the hashtags he uses, "fino alla fine" is also a club motto of Juventus.
Not all Juventus fans were happy though after a summer which also saw the sales of Paul Pogba, Alvaro Morata and Roberto Pereyra. It would seem that Zaza had really endeared himself to the Old Lady's fans in his time in Turin.
se ne andato POGBA e non mi ha disturbato tanto quanto @SimoneZaza al westham ..CIAO GRANDE !! ti auguro tutto il bene del mondo— Robertotaiwan (@robertotaiwan) August 28, 2016
"Pogba leaving didn't bother me anywhere near as much as @SimoneZaza going to West Ham ..Goodbye legend! I wish you all the luck in the world"
Just as his arrival at the London Stadium has received some ridicule after his infamous and bizarre penalty miss against Germany at Euro 2016, some Italians are unwilling to let him forget the blunder so soon either.
"Simone #Zaza is officially a #WestHam player. Excuse us but we just can't forget about this."
"Simone #Zaza is going to dance, erm, play at West Ham #ciaoZaza"
Clearly, though, West Ham's new striker was generally well thought of in Italy and particularly at Juventus even as a back-up option. Slaven Bilic will be hoping that his performances can endear him to the Hammers fans just as much as a former Italian striker and club legend, Paolo Di Canio.
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