The victim has been identified as 73-year-old William Garthaus Jr.
It happened in the 400 block of Walnut Street around 7 a.m.
Sue Naticchia was out for her morning walk with her dog when she smelled smoke, and she saw it.
"I noticed it was coming from the green bungalow, and I do know the gentleman lives alone," she said.
Naticchia didn't have her cell phone, so she frantically got someone's attention to call 911.
"I tried to flag down two people. I'm in the middle of the street yelling, 'Help! Help me!'" she said.
Two police officers and two EMTs arrived ahead of the firefighters.
They found Garthaus, who was the sole resident of the house, unconscious just inside the front door.
They pulled him from the burning house and started CPR.
"A very heroic effort by all four of them to get in there and ascertain that there was nobody else in the dwelling and pull the one gentleman who was in there out," said Chief Patrick Gorman of the Haddonfield Fire Department.
The four first responders, two police officers and two EMTs, who pulled Garthaus out were treated for smoke inhalation.
The fire chief says there is significant damage to the back of the house.
Officials are investigating if there were working smoke detectors in the house.
Naticchia said she didn't hear anything when she came upon the scene.
"I feel sad that they couldn't save him. It was a shame," she said. "I think neighborhoods have to keep an eye on each other. I think, hopefully, that's what we've learned today."
A search of the home revealed that Garthaus' cat also died in the fire.
The cause of the fire remains under investigation, officials said, though at this time it does not appear to be suspicious.