The former Gamba Osaka star and Japanese international joined the Italian club after the 2006 World Cup from French club Grenoble.
The 28 year-old has failed to impress in Italy.
Poor form as well as injuries have limited his appearances and he has failed to score a single goal in two seasons.
"Unfortunately, there was not much room for him at our club," Cairo explained.
Oguro is expected to return to Japan.