LONDON More than half of women (54 percent) questioned in a survey thought rape victims should in some cases bear responsibility for their attack.
One in eight thought that dancing provocatively, flirtatious behaviour, or wearing revealing clothing made them partly to blame.
More women than men also thought that dressing sexily made the victim accountable for the assault.
The online poll of 1,061 men and women aged 18 to 50 in London, called "Wake Up To Rape," was carried out for Haven, which runs three sexual assault referral centres in the capital. Of the total questioned, 712 were women and 349 men.
A fifth of the women said the victim was partly responsible if they went back to the assailant's house and a tenth said taking a drink from a stranger had unforeseen consequences.
Twenty percent of women surveyed said they would not report a rape to police, with half of those citing shame or embarrassment as a reason.
Experts said the findings supported anecdotal evidence that a prevalent "blame culture" among women stopped them coming forward.
"Unfortunately, women have bought into the idea that sometimes the rape victim is to blame. Under no circumstances is a woman at fault for being raped," said Dr Jan Welch, clinical director at one of the Haven centres.
"Coping with the emotional trauma of rape or sexual assault is made even harder when the victim is made to feel responsible for what's happened."
Amnesty International called the findings alarming, but unsurprising.
It is depressing that ... people are still quick to blame the victim of rape rather than placing the responsibility where it actually belongs -- squarely on the shoulders of the perpetrator," said Amnesty's UK director Kate Allen.
"The government has announced that it will develop an 'integrated strategy' to tackle violence against women and these findings are another reminder of how urgent this is and how proper training, support and resourcing will be vital in making it a reality."
(Reporting by Stefano Ambrogi; Editing by Steve Addison)