The incident occurred shortly after 3:30 p.m. Thursday in the 5200 block of Whitaker Avenue.
A Loomis truck driver was making a delivery at the Aldi store when he was approached by two armed suspects, according to police.
Police say the suspects were able to disarm the driver and flee with about $1,000. Both suspects were last seen entering a Nissan vehicle and heading towards Roosevelt Boulevard
No injuries were reported.
The theft comes about a week after another theft of an armored car in the city's Port Richmond section. In that case, a Brinks driver was approached by two armed men on the 3700 block of East Thompson Street. Sources say the armed men stole the driver's gun and at least $1.5 million in cash. The culprits were seen fleeing in a black Hyundai west on East Thompson Street.
Earlier this month, robbers got away with $300,000 during a truck heist in Queens, New York. In another incident in May, an undetermined amount was taken in New Castle, Delaware.
It's still unclear if any of the cases are connected.
"The detectives will look into the other Philadelphia case earlier in the week, but they'll also contact the other police agencies in other jurisdictions to see if it's a similar method of operation," said Philadelphia Police Chief Inspector Scott Small.
Anyone with information is urged to contact Philadelphia police at 215-686-TIPS.
(Correction: A previous version of this story reported $100,000 was taken from the truck.)