The quake hit at a depth of around six kilometers (four miles), on the central island of Leyte, the US Geological Survey said.
There was no immediate warning of a tsunami, the Pacific Tsunami Warning Center said.
Marlon Tano, a Leyte farmer and journalist, told AFP the quake knocked him off his feet at his eggplant farm in Borauen, a town near the quake's epicentre.
"It was so strong that I fell," Tano said.
"I saw buses and motorcyles stopping on the highway and people getting off them," he added.
Large parts of the island of Leyte were devastated by super typhoon Haiyan in November 2013.
Huge tsunami-like waves smashed the city of Tacloban and nearby areas, leaving 7,350 people dead or missing.
In February, a 6.5-magnitude quake killed eight people and left more than 250 injured outside the southern city of Surigao.
The following month a 5.9-magnitude tremor killed one person there in March.
Before the Surigao quakes, the last lethal earthquake to hit the country was a 7.1-magnitude tremor that left more than 220 people dead and destroyed historic churches when it struck the central islands in October 2013.
The Philippines lies on the so-called Ring of Fire, a vast Pacific Ocean region where many of Earth's quakes and volcanic eruptions occur.
