The Umbrella singer leads Eminem and Lady Gaga for the most nods, while Bruno Mars and Justin Bieber were also handed double-figure nominations at a ceremony on Wednesday in Las Vegas.
Rihanna is up for Top Hot 100 Artist, Top Female Artist, Top R&B Artist and Top Dance/Electronic Artist, while her Love the Way You Lie duet with Eminem, places her as a contender in six song categories.
Eminem is a finalist in 16 award categories, including Top Billboard 200 Artist, Top Artist, Top Male Artist and Top Rap Artist, and Lady Gaga follows as a finalist in 12 categories.
Mars and Bieber are up for 11 awards each.
The Billboard Music Awards will take place in Las Vegas on May 22, 2011.