Wearing a fitted black miniskirt that accentuated her curves, a black and white printed blouse, a leather jacket and black platform pumps
Kelly, 26, walked a flirty pink runway with Lourdes in front of a crowd of admirers fans.
Lourdes, 14, was dressed in a yellow and white mini dress with red lipstick and her long, black hair hanging loose.
The party, held at a Macy's department store in New York City, included a runway show and an appearance by the Material mum herself.
Although Madonna, 53, left the hosting duties to Kelly and Lourdes.
While the line launched last year, Kelly took over the spokes model job in February, after Gossip Girl wild child Taylor Momsen, 18, proved slightly too edgy for the line.
In an interview Momsen described the Material Girl look as similar in style to that of a 'high-class hooker' and she was replaced a short time later.
When Kelly was named as her replacement, Madonna said: 'Kelly represents a true Material Girl. She is edgy, cool and has a unique sense of style that Lola and I love.'
The realilty TV personality was featured in a series of glossy ads shot in Manhattan's East Village neighbourhood.