Beyonce is one red hot mama!

Blue Ivy's mom stepped out for the first time since giving birth in a form-fitting Alice By Temperley red dress ... accentuating her bootylicious curves in all the right places.

The sexy songbird, sporting blue nail polish, is in New York to celebrate hubby Jay-Z's performance at Carnegie Hall ... a show benefitting the United Way of New York City and the Shawn Carter Scholarship Foundation.

We're lovin' B's golden Alexander McQueen clutch and sparkly Louboutin heels. Stunning!