The United States Geological Survey said the earthquake hit at an approximate depth of 20 kilometers (12 miles) early Tuesday local time.
The epicenter was in the port city of Durres, about 13 miles from the capital Tirana. Social media videos from the area show several buildings have collapsed.
Police told CNN-affiliate A2 that at least three people had been killed, adding that strong aftershocks were shaking Tirana.
One person died after they jumped from the balcony of a building, officials said, while the other three died in the village of Thumane in western Albania.
Minister of Health Ogerta Manastirliu confirmed earlier in the morning that at least 140 people had been injured.
Schools have been closed in three cities — Durres, Lezhe and Tirana — until further notice.
This is a developing story.