The epicentre was 19 kilometres east of the town of Stolac. Another, 3.7 magnitude tremor was recorded at 23.14 pm in the same area.
The European-Mediterranean Seismological Centre registered three aftershocks measuring 3.1, 2.7 and 3.9 on the Richter scale.
The earthquake was also felt in neighbouring Croatia and Montenegro.
According to local health authorities, a 28-year-old woman was killed in Stolac after a rock fell on her house and several people in the region suffered light injuries. The property damage is yet to be assessed.