Members of the Mumbai Press Club said in a statement that they strongly condemn Ranaut's language and behaviour towards the news media, particularly towards PTI journalist Justin Rao.
On Sunday, Ranaut launched an attack on the reporter even before he could ask his question during a song launch event of her film "JudgeMentall Hai Kya", the statement added.
She accused the journalist of running a "smear campaign" against her and her last release "Manikarnika".
Instead of making amends, the release said, Rangoli Chandel, Ranaut's sister and manager, launched an "abusive" attack against news media on Twitter.
While "JudgeMentall Hai Kya" producer Ekta Kapoor apologised for the incident, Ranaut has refused to do so.
"The Entertainment Journalists' Guild, which first raised the issue, has pointed out that this is not the first time Ms Ranaut and her manager-sister have insulted and abused journalists. It has become part of their unprofessional conduct," the release said.
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"The Mumbai Press Club stands fully behind the Guild to demand Ms Ranaut tender an apology to Justin Rao and the other journalists for her behaviour. We also fully support their call for a complete boycott of her events," it said.
The Mumbai Press Club said it had examined the footage of the press conference. While the reporter was "fully composed", Ranaut was abusive and insulting even though as a journalist he was fully within his rights to criticise her work.
"A job of a journalist is to provide independent assessment of entertainment content; and critical commentary cannot be reason enough to lose control, turn against the media and hurl expletives," the release said, adding that if necessary members of the club will take up the matter with "various associations of filmmakers"
"Since this has been a serial problem, we will also examine the option of pressing criminal charges of abuse, defamation and intimidation against Kangana Ranaut; as well as seek civil compensation for preventing journalists from carrying on their professional work," the release said.
On Sunday, Ranaut had also accused Rao of writing negatively about her film "Manikarnika".
The journalist denied the allegations and the actor's claim that he personally messaged her and spent three hours in her vanity van. He said he met the actor briefly for an interview and there were no personal messages.
On Thursday, Ranaut posted a video saying that she would not apologise.