Fabregas was a free agent after leaving French Ligue 1 side AS Monaco at the end of the 2021/2022 season.
Fabregas has been bedeviled by injuries in recent seasons and made just five appearances across all competitions for Monaco last term.
But the 35-year-old is still keen on prolonging his career and has penned a two-year contract with the Serie A hopefuls, despite interest from a number of Major League Soccer clubs.
Como finished 13th in Serie B last season.
"First of all, I would like to thank the club for believing in me and my family, who have always been willing to follow me in my career," the midfielder said at his presentation on Monday.
"I came here to play in the best possible way and win as many games as possible . This is my priority. If I felt that it was no longer this, I would hang up my boots.
"I want to bring Como back to where it deserves to be: in Serie A. I know the club wants to be competitive, it has shown ambition since the first day."
The former Chelsea and Arsenal star, who also played for Barcelona, has also invested in Como by becoming a shareholder.
Como's CEO, Dennis Wise, who is also a former Chelsea midfielder, added: “I think it will be an excellent deal."
"He has decided to marry this project for the next two years and we are very happy with this choice.
"I would like to thank his attorney Darren and his wife Daniela for convincing him to accept the Como proposal.
"He will become a shareholder of the company, he came here for that too. He will be here longer than expected, he wanted to join the club for our ambitions: to fix the stadium, open a new sports center and get to Serie A."
Fabregas earned 110 caps for Spain, and was part of the sides that won two European Championships and the 2010 FIFA World Cup.
