The U.S. Geological Survey reports that the quake was centered 22 miles North-northwest of the port of Hualien.
The quake, which was six miles deep, struck at 11:36 a.m. local time.
No immediate reports of significant damage or injuries.
Earthquakes frequently rattle Taiwan, but most are minor and cause little or no damage.
However, a magnitude-7.6 earthquake in central Taiwan in 1999 killed more than 2,300 people.