The full report into his behaviour, which has just been published, says Raab acted in an "intimidating" and "insulting" manner.
Prime Minister Rishi Sunak, who received the report yesterday, says he has accepted Raab's resignation "with great sadness".
Raab, who was also justice secretary, had promised to resign if the inquiry found evidence of bullying and has said it "is important to keep my word".
But he has hit out at the findings, saying it sets a "dangerous precedent for the conduct of good government"
He says the report dismissed all but two of the bullying claims against him.
Labour leader Keir Starmer accuses Rishi Sunak of weakness, saying he should have sacked Raab first.
Complaints into Raab's behaviour from several civil servants were investigated by senior lawyer Adam Tolley KC.
Raab, who was also justice secretary, had promised to resign if the inquiry found evidence of bullying and has said it "is important to keep my word".
But he has hit out at the findings, saying it sets a "dangerous precedent for the conduct of good government"
He says the report dismissed all but two of the bullying claims against him.
Labour leader Keir Starmer accuses Rishi Sunak of weakness, saying he should have sacked Raab first.
Complaints into Raab's behaviour from several civil servants were investigated by senior lawyer Adam Tolley KC.