Lorenzo Vinciguerra took advantage of a pre-dawn assault by soldiers on his Abu Sayyaf abductors in the jungles of a remote southern island to make his bold escape, the local military spokeswoman told AFP.
"One of them (gunmen) caught up with him as he was running away and there was a scuffle over his machete," spokeswoman Captain Rowena Muyuela said.
"Vinciguerra was slashed on the cheek but he stabbed the other man in the head . . . then the bandits shot at him but he got away."
A Dutch man who was abducted with Vinciguerra, Ewold Horn, was unable to run away because he was too frail and is believed to still be a captive, Muyuela said.
Local military commander Colonel Alan Arrojado said his troops, acting on a tip, had been able to track the gunmen on Jolo island, a known stronghold of the Abu Sayyaf about 1,000 kilometres (600 miles) south of Manila.
"It was in the jungle, in the darkness. I sent a message to the Scout Rangers that they should not shoot randomly. Sure enough, we encountered them," Arrojado told AFP.
An informant later reported to the military that the man Vinciguerra had fought with had died, according to Arrojado, but this could not be confirmed.
Vinciguerra, who was reported to be 47 when kidnapped, was only slightly injured in the scuffle, Arrojado said.
He was taken to a southern military hospital for medical checks.
Photos released by the military showed him lying in a hospital bed with a bandage wrapped around his bearded face.
He appears much thinner than in photos taken shortly before he was kidnapped, but military officials gave no more information about his condition.
Vinciguerra and Horn, reported to be 52 when he was seized, were on an expedition to photograph rare birds on the remote Tawi-Tawi island group in the southern Philippines when they were abducted by unknown gunmen and turned over to the Abu Sayyaf.
The Abu Sayyaf is a loose band of a few hundred militants founded with seed money from Al-Qaeda and has been blamed for the worst terror attacks in Philippine history, including the bombing of a ferry in Manila in 2004 in which more than 100 people died.
The group has also been accused of repeated kidnappings of foreigners in the southern Philippines who are usually ransomed off for huge amounts.
Many foreign governments warn their citizens against travelling to the Tawi-Tawis and other islands in the southern Philippines that are regarded as strongholds for the Abu Sayyaf and other Islamic militants.
The Abu Sayyaf claims it is fighting to establish an independent Islamic homeland in the Muslim populated south of the mainly Catholic Philippines.
In July, a video appeared on Youtube in which one of the Abu Sayyaf's leaders, Isnilon Hapilon, pledged allegiance to the Islamic State extremists who have taken control of large parts of Iraq and Syria.
But local authorities regard the group as a non-idealogical band of criminals chiefly focused on the lucrative business of kidnapping for ransom.
It is considered a terrorist organization by the United States, which has provided military assistance and training to Filipino troops to hunt down the group.
Although the Abu Sayyaf usually keep its foreign hostages alive to secure the ransoms, the militants often behead their Filipino captives.
In one rare murder of a foreigner, the militants beheaded American hostage Guillermo Sobero in 2001.
The Abu Sayyaf in October released two Germans they had held captive for six months.
German and Philippine authorities refused to say if a ransom had been paid to secure their release.
But the Abu Sayyaf later posted a video on Facebook showing money which they said was the full 250 million pesos ($5.7 million) they had demanded for the Germans.
The military has conducted a sustained offensive against the Abu Sayyaf since the Germans were released, and Arrojado said Saturday's assault was part of that.
Five Abu Sayyaf fighters were killed in another assault on Saturday only about 15 kilometres from where Vinciguerra escaped, the military said.