The magnitude-7.1 quake that hit at 6:54 a.m. (1154 GMT) was felt across much of the nation, including the capital, Quito.
The U.S. Geological Survey said the quake was centered 110 miles (175 kilometers) southeast of Quito. But it was also very deep - 131 miles (211 kilometers) below the surface - a distance that might have blunted its damage.
Ecuador's national Geophysics Institute reported that some areas shook for almost 10 minutes.
It said several houses were reported damaged in the cities of Guayaquil and Manta, where one person suffered minor injuries.