The 38-year-old former pop star wants the band to reform and rival Britney Spears, who starts her shows in Sin City at the end of this month.
Mel B told American chat show host Ross Mathews: ''I did have a conversation with Geri a couple of days ago saying wouldn't it be cool to do a Vegas spot.
''I already had my show in Vegas. I am championing them to get back together by hook or by crook.''
The 'America's Got Talent' judge, who has released her first single in eight years 'For Once In My Life', also wants a Spice Girls 20th anniversary reunion tour next year to mark two decades since they first formed as a band in 1994.
Victoria Beckham's career as a fashion designer has sky-rocketed since the Spice Girls became famous in the 90's, while Mel C, Mel B, Geri Halliwell and Emma Bunton have worked on TV and music projects.
Mel C's career has seen her duet with 'X Factor' winner Matt Cardle recently and she performed alongside Jools Holland at the Royal Albert Hall last week.
But Geri's comeback single 'Half Of Me' failed to make an impact in Australia, where she appeared as a judge on 'Australia's Got Talent', and she was left ''gutted'' after it sold just 393 copies in its first week.
The girl group reunited for a one-off performance at the London Olympics Closing Ceremony last summer, but Victoria is adamant she wont sign up for any more live work because she wants to focus on her fashion line.
Britney Spears, who turned 32 this week, has just released her eighth studio album, Britney Jean, and is reportedly being paid up to $20 million for her 'Piece Of Me' residency at Planet Hollywood.