The Court of Appeal in London upheld a ban on the store selling a sleeveless T-shirt featuring a photo of the star without obtaining her permission.
In the first successful celebrity case of its kind, three appeal judges agreed marketing the item without Rihanna's approval amounted to "passing off".
In other words, the unauthorised image was damaging to Rihanna's brand.
The star sued Topshop's parent company Arcadia for $5m (£3.3m) back in 2013 over the T-shirts, which featured a photo taken during a video shoot in 2011.
In his ruling in July 2013, Mr Justice Birss found some buyers would have been deceived into buying the top because of a "false belief" it had been approved by the singer.
He said it was damaging to her "goodwill" and represented a loss of control over Rihanna's reputation in the "fashion sphere".
Topshop lawyers had urged the appeal judges - Lord Justice Richards, Lord Justice Kitchin and Lord Justice Underhill - to rule that Mr Justice Birss had misunderstood the law on celebrity merchandising.
Analysis - Clive Coleman, Legal Affairs Correspondent
Rihanna's Talk That Talk was the 10th best-selling album of 2011 in the UKA first reaction to today's ruling might well be that it is Rihanna's image, so why shouldn't she be able to stop people using it? Well, actually there is no "personality/image right" in UK law. The photographer who takes a photo owns the copyright, not the celebrity. There is generally no right to control its exploitation.
Rihanna's case was different because she had previously had an association with Topshop - customers could win a shopping trip with her. Also, the photograph on the T-shirt was similar to those used to promote her album, Talk That Talk. That increased the chance customers would be misled into think she had endorsed the product. That's known as "passing off".
T-shirts you see in street markets bear images of bands from the Beatles to One Direction. No-one thinks those bands have anything to do with those t-shirts. So there is no "passing off".
The key question is whether the unauthorised use of the image misleads the public. It will only be in very specific circumstances that it does.
Today's ruling doesn't establish general image rights for celebrities.
Rihanna's victory does not necessarily pave the way for other celebrities to sue companies who use their image without permission, copyright lawyer Paul Joseph told the BBC.
"The court was very keen to stress that there were specific facts that made Rihanna's case stronger than usual."
Mr Joseph said previous links between the singer and the store - which included competitions and publicity appearances - may have implied an official collaboration.
Additionally, he said: "The image that was used here was actually from the publicity material from her Talk That Talk album.
"These particular factors would make the public think this T-shirt had been authorised by her."
The BBC's legal correspondent Clive Coleman said this was the first reported English case of a celebrity claimant successfully relying on passing off to claim compensation for the unauthorised use of their personal image on merchandise.
