The music superstar swapped a catwalk for a stage separated into compartments, which the models moved between to the sound of loud hip hop.
The clothes on offer for her spring/summer 2013 line were of a raunchy street-style theme - with bra tops, dresses slashed to the thigh, tummy-baring tank tops and thigh-high boots.
Rihanna finally came out at the end to give the designer's customary bow and was dressed in a short black dress, sparking necklace and plenty of bracelets.
The show, at the Old Sorting Office in Central London, was due to start at 9pm but did not start until almost an hour later.
Journalists and photographers were made to stand outside for almost two hours before they were allowed in to set up their equipment.
Earlier this week Rihanna expressed her excitement about her foray into the fashion world, and said she was looking forward to fans finally seeing her designs.
She said on Twitter: "My first fashion show!!! My designs will walk the catwalks of London Fashion Week in days!! It's gonna be MAJAH! #RihannaForRiverIsland."
She added: "Fashion gods will be in the building!! #FRONTROWLIFE #YouCantSitWithUs #RihannaForRiverIsland Can't wait for you to see it!!!"
The highly anticipated collaboration goes on sale on March 5, but the show gave fans an idea of what to expect.