McGowan, 46, is a face of the MeToo movement after she went public with her claims that Harvey Weinstein had raped her,
She is also an outspoken critic of presidential candidate Biden and his supporters after she sided with his accuser Tara Reade, who claims the former VP assaulted her in 1993. Biden has denied any wrongdoing.
In response to Biden's speech on Friday night where he said Donald Trump had "cloaked America in darkness for much too long", McGowan tweeted: "You are the season of darkness @JoeBiden @dnc. You are monsters. You are frauds. You are the lie."
"What have the Democrats done to solve ANYTHING? Help the poor? No. Help black & brown people? No. Stop police brutality? No. Help single mothers? No. Help children? No. You have achieved nothing. NOTHING. Why did people vote Trump? Because of you motherf**kers," she added in a follow-up tweet.
The comments drew criticism from thousands of users defending the Democratic party including Milano herself.
Milano, 47, responded with a 26-tweet thread of "all the things the Democratic Party has done to make the world a better place", beginning 100 years ago.
A thread of all the things the Democratic Party has done to make the world a better place.
Let’s start here: 1920 19TH AMENDMENT: WOMEN'S SUFFRAGE Under the leadership of Democratic President Woodrow Wilson, the U.S. Constitution was amended to grant women the right to vote. pic.twitter.com/EK60QJm2ia
She claimed Democrats "lead the way" on issues of abortion, women's rights, healthcare, racial justice and LGBTQ rights, before firing back at McGowan saying she was the true "fraud".
"Rose and anyone bleating the same 'dEmOcRaTs DoNt HeLp PeOpLe' nonsense, your lies are going to hurt people less privileged than you. It's the kind of thing an ACTUAL fraud would do. Thousands of people are dying a day but you go on with your hyperbolic attention-seeking tweets," Milano said.
In this new tit-for-tat war, McGowan sent another explosive tweet, accusing Milano of hijacking the MeToo movement from its creator Tarana Burke and claimed she was a toxic person to work with.
"You stole #metoo (a brilliant communication tool, not a movement) from Tarana (Burke). You co-opted my movement, the Cultural Reset, for fame, jealous of me for outing my rapist. You made 250k per week on Charmed," she tweeted.
"You threw a fit in front of the crew, yelling, 'They don't pay me enough to do this sh*t!' Appalling behaviour on the daily. I cried every time we got renewed because you made that set toxic AF. Now, get off my coattails you f**king fraud."
There really is a lot of Milano Derangement Syndrome out there. But none of you will ever, ever silence me. Can’t stop won’t stop. https://t.co/g8KauOX6KH