The offshore quake occurred at 3.47 pm (0847 GMT), with the epicenter 91 kilometres (56 miles) southwest of the provincial capital Banda Aceh, said Syahnan, chief metereologist in Aceh.
The quake was felt strongly at Calang in West Aceh but there were no reports of casualties or damage.
"In Calang residents ran out of their homes in panic," he said.
Aceh was the hardest hit by the 9.3-magnitude quake off the coast of Sumatra that triggered tsunamis on December 26, 2004. The waves killed about 220,000 people around the Indian Ocean.