The fire broke out just before 1:30 a.m. at the Park Circle Apartments on the 8000 block of Roosevelt Boulevard.
Firefighters arrived to flames showing inside a basement apartment.
They quickly doused the flames and got the fire under control.
Officials say a woman inside the apartment suffered from burns and smoke inhalation.
She was rushed to the hospital in critical condition.
So far, there is no word on what sparked the blaze.