Dulmatin has a $10m US bounty on his head
Experts in the Philippines are carrying out tests on a body to determine if it is one of South East Asia's most wanted militants, Bali bomb suspect Dulmatin.
Troops found the body after an informant led them to a jungle grave in the southern province of Tawi-Tawi.
Reports had suggested Dulmatin had been injured in a clash with troops there in late January, the military said.
The Indonesian national is believed to have played a key role in the Bali nightclub attacks of 2002.
Teams from the Philippine police and America's FBI were now in the southern city of Zamboanga to carry out tests, an official said.
Born in Central Java in 1970
Believed to be protégé of Azahari Husin, JI's former top bomb maker
Named as bomb maker in 2002 Bali bombings
Also suspected of involvement in Jakarta Marriott Hotel attack in 2003
US put $10m bounty on his head
Thought to have fled to southern Philippines in 2003 to avoid arrest
"As of now, we are conducting a DNA test to confirm if it is really his body," Maj-Gen Ben Dolorfino told journalists.
Samples from the body would be compared with those from Dulmatin's children, who were found in the southern Philippines in two groups in October 2006 and May 2007.
The body had gunshot wounds consistent with injuries the militant is reported to have received in the 31 January clash, Maj-Gen Dolorfino said.
Dulmatin is believed to be a key member of regional militant group Jemaah Islamiah and to have helped build the bombs that killed 202 people in Bali.
He and another Bali bombing suspect, Umar Patek, fled to the southern Philippines in 2003.
Philippine military officials say they have received shelter from Muslim militants belonging to the Abu Sayyaf group.
The US has offered a $10m (£5m) reward for Dulmatin's capture.