Collins has asked that the portrait be relocated to the National Party's parliamentary base on the third floor of Parliament house.
"He belongs in Parliament because, if you know your history, he was one of the very few political leaders who was prepared to stand up to the Nazis and fascists in World War II," Collins said.
"I just think the Greens are uninformed by history. What do they want him replaced with - do they want Stalin up there?" Collins said.
The Green Party has responded to Collin's criticisms, saying the portrait was being replaced by a new piece by tangata whenua artist Marilynn Webb.
It was purchased by Parliament's art committee, which is chaired by Green MP Dr Elizabeth Kerekere. Kerekere had asked the committee about moving the Churchill portrait.
"We are really excited about displaying artwork by Marilynn Webb outside the Green Party office and the hallway to the Speaker's Gallery."
Kerekere said the Churchill portrait was "a significant work" and would remain on display in another public area of Parliament.
She also questioned Collins' decision to raise it as an issue: "After saying she wanted to refocus on the important issues, it's disappointing to see Judith Collins instead focusing on the placement of a painting."
The Churchill portrait has long hung in a public area on the second floor of Parliament outside the doors which lead to the public galleries above the Debating Chamber.
Members of the public would walk past it on their way to watch Parliament.
Despite hanging in a public part of the building, the portrait hangs directly outside the Green Party's parliamentary offices. The party has only recently moved into those offices, after a reshuffle of parliamentary office space.
Collins was unhappy with the move.
"I'm actually really pissed off. I'm disgusted that Parliament has actually let this happen," said Collins.
"This is a public area of Parliament and the Greens get to dictate that Winston Churchill, the politician who had the stamina, the courage, the fortitude to stand up against fascism when others around him were appeasing.
"They get to determine whether or not he's there. It's disgraceful."
Collins said she would not fight the Greens on the beaches, but she just wanted someone to take the picture of Sir Winston home.
