The superstar is encouraging fans to vote online for their favourites.
Madonna released the teenage clothing range, designed in collaboration with her daughter Lourdes, last year with actress Taylor Momsen as the collection's poster girl.
She is now looking for a replacement for the Gossip Girl star, and a post on the brand's website is urging fans to cast their vote to decide who gets the job.
A message on the site titled 'Desperately Seeking material girl', references lyrics from Madonna's famous song of the same name and reads, "Living in a material world, we all need material girls. Looking for the hottest girl on the scene. She is never afraid. Hollywood is calling the next girl!... Wanted: Next big star. She makes her own fashion statement - trendy, but cool, young and hip."