Fire crews were called to the home on the 5300 block of Frankford Avenue shortly after 8:15 a.m.
First responders reported heavy fire showing in the rear of the two-story home.
Crews rescued the homeowner, 84-year-old John "Jack" Blitchford, who was trapped in a bedroom.
"They rescued one elderly male and this elderly male was transported to an area local hospital in unstable condition," Philadelphia Fire Department Executive Chief Richard Davison said.
Blitchford was taken to Temple University Hospital where he was pronounced dead a few hours later.
Blitchford was a father of four, a grandfather, the owner of Jack's Auto Repair and a longtime fixture in the neighborhood.
Dave Mauslof called him "Pop" because Blitchford had taken him in when he was homeless and given him a job.
"He means the world to me. I don't what I'm going to do. I busted through windows to try to get him out," Mauslof said.
Another elderly man, who had been Blitchford's longtime friend and Navy buddy, was also staying at the house.
He escaped and was treated and released from Temple University Hospital.
The fire was placed under control within a half hour however a tax preparation business on the second floor was also heavily damaged.
As the bereaved family surveyed the scene, many neighbors stopped to recall Blitchford's generosity.
"I knew him for like 20-something years. He cared about everybody. He's a very sweet man," neighbor Mary Seeger said.
Firefighters found no evidence of working smoke detectors inside. The cause of the blaze remains under investigation.