The actress, whose eldest son Rodney, Jr. was diagnosed with the developmental disorder, switched on blue lights at the Little Nell gala in Aspen, Colorado on Sunday (01Apr12) to mark the annual fundraising drive.
She took to Twitter.com to share a photo of herself at the event, writing, "In Aspen and just pulled the switch to light up the mountain blue (for) autism awareness!"
Braxton, whose nine-year-old son Diezel has autism, also tweeted statistics about the condition as well as information about major buildings around the world 'lighting up' with blue bulbs for World Autism Awareness Day.
She also asked followers to don blue clothing for the occasion, writing, "I encourage everyone to wear a piece of blue to show support for Autism Awareness Day! It's spring, blue goes great with everything!"