No ransom was paid for the release of 63-year-old Eugenio Vagni, Foreign Minister Franco Frattini said in an interview with Italian state TV. Frattini gave no details about how Vagni was freed.
Frattini also expressed gratitude that no government attacks were launched to free the hostage.
The minister said Vagni, now in the care of the Italian Embassy in the Philippines, would be sent to Italy as soon as possible.
Vagni had been in Abu Sayyaf custody since Jan. 15, and troops had been ordered to rescue the Red Cross worker, who suffers from hypertension and a hernia.
The head of the Philippines' national Red Cross, Sen. Richard Gordon, said Vagni was "in relatively good health."
He was abducted with two other Red Cross workers after they visited a water supply project in a Jolo jail. The two other captives, a Swiss and a Filipino, had been freed earlier in the year by the militants.
The International Committee of the Red Cross had repeatedly appealed for Vagni's safe release.
Abu Sayyaf, which has about 400 fighters, is on the U.S. list of terrorist organizations because of its many attacks, including those that have victimized Americans, and because it has received funds and training from al Qaeda.
The group and its allies have turned to kidnappings to make money in recent years, raising concerns among Philippine and U.S. security officials that ransom payments could revive the group, which has been weakened by years of U.S.-backed offensives.