Como reached agreement with Fiorentina on the final day of the window, with head coach Cesc Fabregas landing the forward he had pushed hard to sign throughout the summer.
The Italy international leaves Florence having become one of Serie A's more prolific finishers over the past two seasons, and he committed his future to Como until 2031 as part of the switch.
Head coach Cesc Fabregas welcomed his new signing warmly, calling him a player capable of lifting the entire squad.
"Moise is an important player, already experienced and ready but still hungry with plenty of room to grow. He has great physical strength, pace and the ability to lead our attack, qualities that will raise the level of the team," Fabregas said.
"We can't wait to start working together on the pitch."
Kean himself struck a similarly positive tone about the move, praising the environment he had found at the club.
"Here in Como I've found a tight-knit group, lots of players with a real desire to do well, and an excellent project," Kean said. "The coach has big ideas that I really connect with, he gives me huge energy and he's a fantastic person who will help me on my journey. I can't wait to get started and celebrate with the fans at the stadium soon."
Kean joined Fiorentina from Juventus in 2024 for around €15million and made more than 75 appearances in Florence, scoring over 30 goals across his two seasons despite a second campaign disrupted by injuries and inconsistent form for the team as a whole.
He began his career in Juventus's academy, making his Serie A debut at 16, before loan spells at Hellas Verona, Everton and Paris Saint-Germain preceded his return to Turin in 2021.
The move continues an ambitious summer of recruitment at Como, who have already added Nico Paz permanently from Real Madrid along with Trevor Chalobah, Samuele Ricci and several other significant arrivals as the club builds a squad capable of competing in Serie A, the Champions League and the Coppa Italia this season.
Kean's arrival gives Fabregas a genuine focal point for his attack after a summer spent assembling one of the more eye-catching squads outside Italy's traditional elite, with Como determined to build on last season's momentum.
The forward's willingness to push for the move throughout the window, at times publicly making clear his preference for Como over other suitors, played a significant part in the deal eventually coming together on the final day.