The blaze broke out Thursday night at around 11:00 in a three-story brick row home at the end of the 3800 block of West Girard Street in the Mantua section of the city.
When firefighters arrived they found the building engulfed in flames and smoke.
It took about 20 minutes for crews to gain control of the fire.
While firefighters battled the flames they also pulled the trapped man out of the house.
He was rushed to the Hospital of the University of Pennsylvania where he is in critical condition with second and third degree burns on his arms, chest and face.
Investigators are trying to determine what started the fire.
