The Prime Minister has said any minister found guilty of sexual harassment will be dismissed following reports three members of his cabinet are under investigation.
During Prime Minister's Questions Green party MP Caroline Lucas said: "Fifty six members of this house are under investigation for sexual misconduct, and that includes three cabinet ministers.
"The Prime Minister has just rightly said that there can be no place for sexism and misogyny in this house.
"So can he now confirm if he considers sexual harassment, apparently unlike bullying and lying, is grounds for dismissal under the ministerial code."
The Independent Complaints and Grievance Scheme (ICGS) has received 70 separate complaints, the Sunday Times reported.
The allegations range from making sexually inappropriate comments to more serious wrongdoing, with at least one complaint believed to involve criminality.
Mr Johnson replied: "Of course sexual harassment is intolerable and it is quite right that members should have a procedure where they can bring that to the attention of the house authorities...Of course it is grounds for dismissal."
At Prime Minister's Questions, Labour leader Sir Keir Starmer called on Mr Johnson to agree there was "no place" for misogyny in modern Britain.
It followed the Mail on Sunday printing claims made by an unnamed Tory MP that the deputy Labour leader crossed and uncrossed her legs to distract Mr Johnson during PMQs.
Sir Keir said: "I know the Prime Minister will have whipped his backbenchers to scream and shout and that is fine.
"But I hope he has also sent a clear message that there is no place for sexism and misogyny or looking down on people because of where they come from in his party, in this House, or in modern Britain."
Mr Johnson replied that he had "exchanged messages" with Labour deputy leader Ms Rayner at the weekend after a Mail On Sunday article about her.
He added: "I repeat what I said to her, there can be absolutely no place for such behaviour or such expression in this House and we should treat each other frankly, with the respect that each other deserves."