After more than 500 fines were handed out, Victorian Premier Daniel Andrews says restrictions could be tightened if people don't stop breaking the rules.
The state recorded 238 new coronavirus cases in the past 24 hours.
A woman in her 90s died overnight – bringing the number of deaths in the state to 27. There are 105 Victorians in hospital, up 20 from yesterday, and 27 people in intensive care.
Andrews said the situation was "very, very serious" and called out more than 500 Victorians who have been fined in the past week for going against the lockdown rules.
"If people do not do the right thing then we will have to move to additional restrictions being put in place and potentially prolong these restrictions," he said.
In New South Wales, two more pubs have shut down in Sydney as a cluster in the city continues to spread.
The Wests League Club and the Macarthur Tavern, have closed overnight after infected customers visited over the weekend.
Despite an increasing number of Covid-19 infections being linked to a Sydney pub cluster, NSW Premier Gladys Berejiklian has ruled out sending her state back into lockdown.
Australia has recorded a total 10,061 cases of Covid-19, with 4224 in Victoria, 3316 in New South Wales, 1071 in Queensland, 443 in South Australia, 636 in Western Australia, 228 in Tasmania, 113 in the Australian Capital Territory and 30 in the Northern Territory.