Authorities said a second suspect fled the scene and remains on the loose.
It happened at the 7-Eleven store on the 200 block of N. Pine Street late Thursday night.
This is not the first time this location has been robbed. It was the third.
But in this latest incident, the would-be robber would be met with a police officer who was inside the store.
Police in Bucks County and the FBI had recently created a task force to look into multiple 7-Eleven robberies that have occurred in the area.
Am officer who happened to be on that task force ended up getting a firsthand look at the very robberies he was investigating.
"The cops around here are awesome. They go into harm's way all the time. I'm really proud of them," said customer Jeff Hoerger of Holland.
Police said the officer shot one of the suspects who was allegedly robbing the store.
The suspect was injured and taken to hospital where he is expected to survive, authorities said.
The store was temporarily closed after the attempted armed robbery Thursday night.
On Friday morning, one by one, customers walked up to the entrance of the 7-Eleven, yanked on the door, then read the sign.
"I'm shocked. I can't believe this happened in our town," Erin Gansworth of Langhorne said.
"That's pretty scary you know when you're in the suburbs you don't really think that should happen out this way," Vic Patterson of Langhorne.
The search continues for the second suspect.