Buildings swayed and doors shook across the African nation, but there was no immediate report of injuries.
The US Geological Survey said the magnitude 7.5 quake struck, with its epicentre 225 kilometres south-west of Beira.
It was felt as far away as Durban, in South Africa, and Harare, in central Zimbabwe.
"Somebody just called to say a building collapsed in Beira," a reporter at the state Mozambique radio station in the capital Maputo said. But he had no further information.
In Beira, a hotel manager said the quake sent the mainly South African tourists running terrified from their rooms as the building began moving, but nobody was hurt.
"It felt like the building was going to fall down and it went on for a long time, the trembling," Tivoli Hotel manager Johana Neves said.
She said panicked guests had returned to their rooms. But Antonio Dinis, who also was at the hotel, said the streets were full of people afraid to go back home or sleep.
In Maputo, hundreds of people fled their homes into the streets, as they did in Chimoyo, about 480 kilometres west of Beira near the border with Zimbabwe, and at Tete, which neighbours Zambia and Malawi, the Mozambique radio station said.
The quake was shallow, which increases the potential for damage, said Dale Grant, a geophysicist with the USGS National Earthquake Information Centre in Golden, Colorado.
"It was felt very widely in the epicentral area, though it's not a very heavily populated area," Grant said. "There is certain to be damage, but so far, we've had absolutely no word of damage."