Among the crowd was somebody carrying a fake gallows with three nooses strung from it.
Included in the speakers scheduled to address the crowd is former Liberal MP Craig Kelly, who is now a part of Clive Palmer’s United Australia Party.
Taking the stage, singer Claire Woodley dedicated her performance to “the victims of Satanic ritual abuse”.
She then sang a song co-written by her father Bruce, ‘I Am Australian’.
Allegations of Satanic ritual abuse are a common thread in the QAnon conspiracy theory.
The crowd is protesting the Public Health and Wellbeing Amendment (pandemic management) Bill 2021, which passed the lower house in October.
It is expected to face a vote in the upper house next week.
The Victorian opposition has claimed the bill would hand the premier too much power and discretion in pandemics.
COVID-19 cases are continuing to climb in Victoria, with another 1221 cases recorded in the past 24 hours.
There are 405 people in hospital with the disease. Four people died with the virus in the past day.
Eighty-six per cent of Victorians over the age of 12 are fully vaccinated.