His Liberal colleagues voted this morning to impeach him in a ballot in the banquet hall, where Finn was not present.
The move forces Finn onto the cross bench in the upper house of the Victorian Parliament.
Opposition leader Matthew Guy said Finn’s membership had “terminated”.
“This is not something the party has done lightly,” he said.
“The Victorian Liberal Party welcomes a wide and diverse range of views.
“But it also reasonably expects all members to be team players and to keep standards high in their public discourse.”
Guy said it was a disappointing result but added that it was about Finn’s behavior, not his beliefs.
“It’s about not navel-gazing the Liberal Party in federal elections or other matters, it’s about moving forward and being a sensible alternative government,” he said.
“It is disappointing that it has come to this, but I expect discipline from all members of the party and it is about respectful behavior.”
As the leader of the infant anti-abortion march, Finn has been criticized for insisting that pregnancies resulting from rape should not be terminated.
Finn was not present at the meeting, but addressed media and supporters outside parliament after the decision.
About 50 supporters applauded Finn by chanting “hero” and thanked him for his service.
“I joined the Liberal Party more than 41 years ago, at the age of 19, it was the Freedom Party, the Human Rights Party,” said Finn.
“What we have seen today is a statement from the leader of our party that the party I joined more than 40 years ago is dead.
“That’s the problem we have. The party isn’t in Victoria anymore.”
Finn has been a member of the Legislative Council since 2006.
He was a member of Tullamarine’s now abolished House of Representatives between 1992 and 1999.