Greek media reported that the 35-year-old signed a two-year contract and will be receiving two million euros annually for his services.
Cambiasso played 31 matches for Leicester last season, scored five goals and was voted the club's player of the year.
However, he opted not to renew his contract with the English side.
From 2004 to 2014 he played 315 times for Inter Milan, scoring 41 goals.
He has also played for Real Madrid, River Plate and Independiente.
Cambiasso was capped 52 times by Argentina between 2000 and 2011.