Some 20 per cent have seen the images online while another one per cent viewed them in foreign magazines, the YouGov poll of 1,600 people found.
The publication of the images, taken while Kate was on holiday in France, prompted the Royal Family to sue French 'Closer' magazine, which first released them.
Nearly three in four of those polled believe the Royal Family's decision to pursue legal action is correct, while 61 per cent believe the paparazzo who took the intrusive pictures should be prosecuted, The Sun reported.
A higher proportion of men than women have seen the images online and the 18 to 24 age group are the ones that have been most prolific in looking up the snaps.
More than one in four men have searched for the photos online, compared to 15 per cent of women.
The survey found that 47 per cent of 18 to 24-year-olds had looked up the images, compared to 32 per cent of 25 to 39-year-olds, 14 per cent of 40 to 59-year-olds, and seven per cent of those aged 60 or over.
A similar poll last week found the British public were overwhelmingly opposed to French magazine's decision to publish the topless photos of Kate, 30.
After days of furore, a French court blocked the future publication of topless photos of Kate and asked 'Closer'magazine to hand over the original pictures to the royal couple within 24 hours.
The court injunction came after William and Kate took legal action against the French glossy magazine for selling and distributing the images.
Apart from the Frech magazine, an Irish tabloid published the controversial pictures.
The photos are still being touted on the open market worldwide, with magazines in Italy, Denmark and Sweden also publishing them.
