The 21-year-old model showed support for the clothes from the 'Right Now' hitmaker's new range by posting a picture herself in a red quilted bomber jacket and black beanie hat from the 80-piece collection, reported Digital Spy.
Accompanying the photo of herself in the Rihanna-designed garments, Delevingne wrote on Twitter, "Well done Rihanna for another amazing collection for River Island."
Rihanna's second collection will be available in stores from September 13.
Delevingne has previously revealed she often asks Rihanna for style advice.