According to the USGS, the earthquake was registered at 10:32 GMT. The epicentre was located 21 kilometres (13 miles) south of the municipality of Guayanilla, at the depth of 12.9 kilometres.
There have been no immediate reports about casualties caused by the earthquake, and no tsunami threat has been issued.
Some households have reported power outages.
Small buildings partially collapsed in the southern part of the Caribbean island nation, according to the Telemundo Puerto Rico channel.
Daños causados por el temblor (5.7)— 🌊🇵🇷La Bori🇵🇷🌊 (@boricualy) 6 января 2020 г.
Gente que viva en Puerto Rico, se han visto muchos temblores así que prepárense bien y tenga cuidado 🥺🙏🏽 pic.twitter.com/s88zdHerMb
The tremor tore down Punta Ventana, a natural rock formation that has attracted tourists to Guayanilla's coastline with its offer of a scenic view.