The `California King Bed` singer has been signed up by the Italian fashion house to appear campaigns for EmporioArmani Underwear and Armani Jeans.
Rihanna - who will appear in ads for the fall-winter 2011-2012 collections, which were shot in New York City and debut in September - follows in the footsteps David and Victoria Beckham, Cristiano Ronaldo, and Megan Fox in representing the brand.
Earlier this year, Rihanna was named as spokesmodel for Nivea.
The cosmetics brand teamed up with the `What`s My Name` hitmaker to celebrate their 100th anniversary and released a photo of her posing seductively and apparently naked.
A representative for the brand, Markus Pinger, said: "We are excited to have Rihanna supporting us in our celebration and building a new generation of fans."
The 23-year-old star has previously revealed she likes to shock people with her fashion choices.
Talking about her future look, the 22-year-old star said: "I probably see a lot of menswear, or something extremely, extremely feminine. But I like to play with both. It would have to be so extreme that it`s a look, because I don`t usually like typical ladylike, girly-girly stuff. It would be a look if I were to do it. I always like something that`s a little off, so it`s just not typical or expected."