It happened around 12:30 a.m. Wednesday in the 4500 block of North 18th Street.
Police say the four masked men broke into the house demanding money.
The victim told police one of the men grabbed her newborn child from her arms and threw the baby to the floor.
He was taken to Albert Einstein Medical Center for observation and is expected to be OK.
After getting money and cellphones, police say they fled through the front door.
The suspects made off with $3,500 in cash.
The victim told police she had been out with friends earlier in the evening. She told several people she had just come into a substantial sum of money - $3,500 - which she was keeping in her home.
The investigation continues.