The driver of the bus pulled over at Myrtle and Wilson Avenues after hearing the gunshots.
Police responded to the 911 call and found the victim had been shot once in the torso.
Security cameras at a near bodega recorded the suspect running off the bus wearing a blue hoodie.
The victim was transported to Elmhurst Hospital and is expected to survive, police say.
Anyone with information in regards to this shooting is asked to call the NYPD's Crime Stoppers Hotline at 800-577-TIPS or by texting tips to 274637 (CRIMES) then enter TIP577.