There were no immediate reports of casualties from the earthquake.
The United States Geological Survey (USGS) said the quake struck 69km north-northwest of General Santos, Mindanao.
No tsunami warning was issued after the earthquake by the Hawaii-based Pacific Tsunami Warning Centre.
The Philippines is regularly hit by quakes as the country is on the Pacific “Ring of Fire,” a horse-shoe shaped band of volcanoes and fault lines circling the edges of the Pacific Ocean.
