The quake struck at about 9.15am local time (23:15 GMT) on Wednesday in Mansfield, not far from the provincial capital Victoria.
Prime Minister Scott Morrison said “we have never had reports of serious injuries and that is good news”.
The quake was also heard in South Australia near New South Wales (NSW).
Two earthquakes of 4.0 and 3.1 magnitude earthquakes were followed.
Although this is one of the largest earthquakes in Australia in recent years, it has not caused much damage.
Speaking in the United States, Mr Morrison said the quake was uncommon in Australia and “could be a very disturbing event”.
“If you are found in Victoria, you are in danger. Expect the next earthquake, stay away from damaged buildings and other hazards. Avoid driving, except in emergencies,” said the official.
Earthquake hit during heart surgery
Surgeon Sameer Thakur said he had been performing a heart transplant in Geelong, near Melbourne, during the quake.
“We are in danger of working and we have heard that everything is going well,” he told BBC Newsday.
“I looked around the room, all the IV poles were moving and some of the bonds we had, all were moving.”
He said “fortunately we were in the stage where we could have stopped” until the quake, which enabled them to complete the operation. Melbourne, the second-largest city in the country, is home to an estimated five million people.
The city is currently locked due to a recent wave of coronavirus cases.