It happened just before 8 p.m. on the 1200 block of Diamond Street.
Police say a 25-year-old man was stabbed twice, once in the back and neck.
He was transported to Temple University Hospital and placed in critical condition.
Action News has learned the victim is not a student of the university.
It's still unclear what sparked the attack.
No arrests have been made.
Anyone with information is asked to call police at 215-686-TIPS.