The 'Stay' singer hit Instagram on Tuesday night (9 July) to show off her enviable figure in a teeny tiny yellow bikini with red guitar print from Bang Swimwear (available here, £40) as she sunbathed on a lounger.
She added a caption plugging her Roc Nation record label: "Oh baby I'm a Roc StaR."
Rihanna's fans were quick to compliment her in their droves, with comments ranging from "So freaking HOT" to "Marry me!"
Even film director Judd Apatow, who helmed movies including Knocked Up, got in on the action, tweeting a picture of himself with the caption: "Oh baby I'm a Roc StaR... Me too!"
Judd's picture then prompted pop star Pink to reply, saying: "lol lol lol."
He responded: "I wasn't joking. Was there something funny about my photo? Why the lol? I don't get it."
Rihanna, meanwhile, appeared to be taking a break from her 'Diamonds World Tour', which rolled into Vienna, Austria last night.
Her previous date had been in Poland, where she tried to enjoy a day at the beach with friends, but admitted to feeling like a "caged animal" when her group had to arrange beach umbrellas around them to stop prying eyes watching them sunbathe.
Tonight she'll perform the first of two dates in Monte Carlo, Monaco, before heading back to the UK for a headlining slot at T In The Park, and a few more dates on the 'Diamonds' jaunt.
Watch Rihanna giving us a special sneak peek of her new River Island range!
Check out our fave picks of Rihanna's high summer range for River Island below!
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