The Bajan babe's clothing line will be paraded on the catwalk at the prestigious fashion event on Saturday, 16th February - with items available in shops and online from March.
Vogue has quoted RiRi as saying: "Launching at London Fashion Week is a dream come true for me.
"I have wanted to design my own collection for a long time and to present my collection for River Island alongside all of the other great design talent at LFW is a real privilege."
She added: "I can't wait to see the reaction from my fans and the fashion press!"
The Diamonds singer has previously ventured out into the world of fashion by producing Sky Living TV show Styled To Rock - which is set to hit the US later this year.
Rihanna was also in the news this week after revealing the artwork for her new single Stay - which appeared to feature her snuggling up to rumoured beau Chris Brown.
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