Laura Boldrini was commenting on a post on the Facebook page belonging to the Five Star Movement's leader Beppe Grillo, which asked on Saturday "what would you do if you found Boldrini in your car?"
The question, which accompanied a satirical video and was taken up on the movement's official website, sparked a series of abusive comments, including calls for Boldrini to be raped.
The post was an "instigation to violence, just look at the comments it prompted, nearly all of which were made in a sexist context," Boldrini said in an interview late Sunday on Italian television.
"Those who take part in the blog do not want to debate, but to offend and humiliate on a sexual level. They are almost potential rapists," she added.
The post on former comedian Beppe Grillo's page came in the wake of a fierce fall-out between the Five Star Movement (M5S) and Boldrini over a controversial measure aimed to shore up Italy's public accounts.
On Wednesday, Boldrini used her so-called "guillotine" powers to cut short a filibuster by M5S deputies who were attempting to block the adoption of the complicated decree, which passes part of the cost of scrapping an unpopular housing tax onto Italy's banks.
Her interruption and order for the lower house to vote immediately on the decree sparked fury among the M5S deputies, some of whom reportedly slung sexist insults at her while others stormed government benches, whistled and symbolically gagged themselves.
Grillo has since held an online vote to ask M5S members how they would like to react to the "guillotine", the majority of which voted to demand Boldrini resign.