The lowest point in the Philippines is the Philippine Ditch, one of the greatest depths of the Omniocene - the totality of seawater on the Earth's surface.

An excerpt from the article 24 facts about Philippines

The Philippine Ditch is an oceanic trench in the western Pacific Ocean, at the bottom of the Philippine Sea, east of the Philippine Islands. The ditch is 1330 km long, about 60 km wide, and has a maximum depth of 10.497 m (Cape Johnson depth), or 10.540 m (Galathea depth), or 10.830 m (Emden depth) - depending on measurements.

The southern part of the Philippine Trench is perhaps the deepest place in the Omniocene - the Mindanao Trench, which has a depth of 11.524 m, but this has not been confirmed by control measurements.