The quake struck 60 km (37 miles) northwest of the capital, Manila, at a depth of 40 km (25 miles), the US Geological Survey (USGS) said.
The governor of Pampanga province told a radio station that several people had been killed. Media reported some structures had collapsed and the Clark International Airport, a former US military base, had suffered some damage and had closed, Presstv reported.
Tall buildings swayed in Manila's main business district and some people evacuated their offices.
The Philippines is on the seismically active Pacific "Ring of Fire," a horse-shoe shaped band of volcanoes and fault lines circling the edges of the Pacific Ocean.