The latest quake hit at 4:44 a.m. local time, but there were no immediate reports of damage or injuries.
Wednesday's quake hit off Japan's northeastern coast, and there were no reports of damage or injuries after that quake either.
However, Wednesday's quake produced a 24-inch tsunami that reached the coastal town of Ofunato. Other towns reported smaller waves that reached shore about 30 minutes after the quake, which occurred at 11:45 a.m.
The quake was felt all the way in Tokyo, about 250 miles away.
News and surveillance cameras captured the moment the shaking started.
Japan lies on the "Ring of Fire" - an arc of earthquake and volcanic zones that stretches around the Pacific Rim and where about 90 percent of the world's quakes occur.
The Associated Press contributed to this report.