The Hero hitmaker was on hand at the New Jersey Performing Arts Center to present the R&B icon with a career achievement prize and she couldn't contain her excitement as she waited for the big moment.
Taking to her Twitter.com blog, she wrote, "Still backstage waiting... Hey... I would wait forever for the incredible Patti LaBelle".
When the time came, Carey, who bared her midriff in a cropped black halter neck top and a long black and gold skirt, sashayed onto the stage and gushed about LaBelle, before greeting the veteran Lady Marmalade star with a kiss and a tender hug.
Other honourees at the event included rapper, actress and talk show host Queen Latifah, who was handed the Rock Star Award, and tennis ace Venus Williams, who received the Star Power Award.
The show, which highlights the achievements of exceptional black women, also featured performances from Janelle Monae, Jennifer Hudson, and Kelly Rowland and Eve, who teamed up for a remix of the former Destiny's Child star's latest single, Gone.
The 2013 Black Girls Rock event will be broadcast on America's Bet network next weekend (03Nov13).