Fines will double if Coalition amendments to the Livestock Management Amendment (Animal Activism) Bill pass in state parliament.
Currently the Bill proposes maximum fines of just over $10,000 for any individuals caught trespassing on Victorian farms.
But Nationals leader and Shadow Agriculture Minister Peter Walsh said this fine was too low and a fine for individuals to just under $22,000 would be a strong deterrent and put it in line with NSW laws.
Mr Walsh said the state government had been dragging its feet on the legislation, and improvements were needed.
"There is no justification for why the penalties in Victoria should be significantly less than other states or why river frontage land should be excluded," Mr Walsh said.
"Labor MPs and Independents in Parliament's lower house turned their back on our farmers by blocking the Liberals and Nationals' move to better protect farmers."
Under NSW's Right to Farm Bill 2019, fines of up to $22,000 can be given to anyone who unlawfully enters and disrupts "enclosed lands", along with up to three years in jail.
Secondly, trespassers on NSW farms that have biosecurity plans can be given on-the-spot fines of $1000 while the potential for maximum fines for an individual of up to $220,000 under the NSW Biosecurity Act.
The Coalition had introduced the amendments in the Legislative Assembly but the Bill passed without changes due to Labor's majority.
The Bill is now headed to the upper house where Labor will need cross bench support.
In the debate in the Legislative Council, Nationals Member for Eastern Victoria Melina Bath said the Coalition was also looking to make more amendments to reverse a plan to exclude farmers' river frontage licensed land from protection under the law.
"We believe that if a farmer takes on licensed river frontage, holds that licence, they should have protections equal to if they own their freehold land or if they have leased land from their next-door neighbour," Ms Bath said during the debate.
Labor Member for Northern Victoria Mark Gepp said the proposed fines would be the strongest in the nation and also dismissed the amendments regarding riverfront.
"There has been no evidence whatsoever that animal activism is somehow linked to some form of trespass through licensed Crown waterfrontages," Mr Gepp said.
"Every citizen should be entitled to use licensed Crown waterfrontages - campers, whoever it might be.
"This amendment being advanced by The Nationals and the Liberals has absolutely nothing to do with the bill at hand."
The Greens' Samantha Ratnam opposed the Bill in debate and said the legislation singled out activists and campaigners.
"The bill is supposedly responding to the perceived threat of biosecurity breaches from activists who enter farms and agricultural facilities, but the inquiry found that there had been no reported outbreaks of disease caused by animal activists," Dr Ratnam said.
The debate was adjourned on Thursday, with the bill to be further debated and possibly voted on in the upper house later in March.