Manny Pacquiao is heartbroken over the devastation the Taal Volcano is causing in the Philippines ... and now he's begging for help, saying he'll double anyone's donations to relief efforts.
The small volcano -- located less than 100 miles south of Manila -- began erupting over the weekend ... and it's ravaged the region -- forcing tens of thousands out of their homes.
And, according to reports, there's still concern a massive, hazardous, explosive eruption could happen.
Pacquiao -- who was born in the Philippines and currently sits as the country's senator -- is trying his best to help in relief efforts ... donating food, items and money -- but he's asking for much more.
"Whatever we raise," Pacquiao said in a video message Thursday, "all the donations, whatever it costs, I will double that so we can help more people."
Pacquiao says the disaster hits very close to home for him ... not just because he grew up in the region -- but because he went through homelessness and poverty as a youngster as well.
"I've experienced not having anything to eat and not having a place to sleep," Pacquiao said. "These people need our help."
Per the Philippine Institute of Volcanology and Seismology, the volcano showed signs of "generally weaker" activity Wednesday ... but the threat of earthquakes and a possible explosion still remains high.