The driver was making a delivery at a check cashing store at Rockaway Parkway and Seaview Avenue in Canarsie when the suspect got into the car and pointed something at the driver's head.
The suspect forced him to drive a few blocks before he took the cash and fled.
The FBI and NYPD are investigating.
Law enforcement officials are probing whether the heist is connected to an armored car robbery in the Bronx in 2011. In that case, the driver entered a check cashing business with a bag of money, and was followed by two men, one of whom had a handgun.
The suspects demanded money, and maced the driver during a struggle. The driver fired several shots at the suspects as they fled with cash.
The same armored car company was involved in both robberies.
