The earthquake was located 34 km from Port Vila and struck at 9:13 AM local time.
Some members of the public took to social media to record their experiences.
One spoke of the house shaking while another spoke of running out of the house.
There are no immediate reports of damage.
Today's earthquake is the third big one this week.
The other two that hit on Monday measured 5.3 and 5.1 respectively.