Chelsea and Arsenal legend ended his career with the Italian second division side Como this year.
And he has since been coaching their Under-19 squad after becoming a part-owner in the team with former team-mate Thierry Henry.
Como were without a manager after Moreno Longo was sacked with the side sitting in sixth.
The club announced Fabregas will take charge – initially on an interim basis.
In a statement the club said: “Como 1907 and Moreno Longo have parted company. The search for a new Head Coach begins immediately with Cesc Fàbregas and the current coaching staff taking over duties for the interim period.”
They added that his first training session will be today.
It will be the Spaniard’s first tase of senior football management.
Fabregas made 17 appearances for Como before announcing his retirement at the end of last season.
He said at the time: “It is with great sadness that the time has come for me to hang up my playing boots.
“From lifting the World Cup, the Euros, to winning everything in England and Spain and nearly all the European trophies, it has been a journey that I’ll never forget.
“After 20 incredible years full of sacrifice, dedication and joy, it’s time to say thank you and goodbye to the beautiful game.”
Fabregas, 36, revealed he was hanging up his boots to focus on a long term project with Como.
He said: “A club and a project I couldn’t be more excited about.
“This charming football team won my heart from the first minute and came to me at the perfect time in my career. I will grab it with both hands.
“So after 20 incredible years full of sacrifice, dedication and joy, it’s time to say thank you and goodbye to the beautiful game. I loved every minute.” – The Sun