The 81-year-old songstress fell ill during a charity concert for the Jazz Foundation of America at the Apollo Theater in New York.
Flack was 'able to leave the stage under her own power' before calling an ambulance to the venue in Harlem.
he New York City Fire Department responded to a call of a 'sick person' late Friday evening.
At around 8:50 p.m, an ambulance responded to the location where the Killing Me Softly singer was then transported to a local hospital.
She arrived at the Foundation's red carpet event wearing a heavy blanket and thick scarf while in a wheelchair.
Roberta was also being honored at the annual gala, called 'A Great Night in Harlem.'
We Are Praying For Her Recovery In The Starr Lab!!!