Kean has joined the Goodison Park outfit for an initial fee of £27m.
Kean, who has scored two goals in three appearances for the Italian national team, is Everton’s fifth summer signing, joining goalkeeper Jonas Lossl, Fabian Delph, Andre Gomes and Jean Philippe-Gbamin on Merseyside.
Kean scored six goals in thirteen appearances for Juventus last season, helping them to their eight straight Italian title.
“I am very proud and honoured to wear the Everton shirt. I will give my best to this team,” the Toffees' latest signing told evertontv.
“I was convinced to sign because Everton is a club looking to the future and so am I. I know about the size of the Club. It has big ambition and I will work very hard to help us fulfil what we want to achieve.
“I am used to winning and I want to bring this winning attitude to the team. I hope I will be very good on the field and bring the fans joy.”
Everton have also lost the services of Ademola Lookman and Idrissa Gana Gueye to RB Leipzig and Paris Saint Germain respectively.
“A striker was one of our priority signings this summer," Everton manager Marco Silva said in the wake of Kean's signing.
“Moise is strong, fast, with many good qualities as a striker and he is just 19 years old. He has talent and he is ready to work, ready to improve our squad and gives us different solutions.
“Of course he was at a big club, now he’s come to another big club and is ready to fight for this challenge and to give everything to Everton Football Club.”