It happened around 2:30 Saturday morning near the intersection 54th Street and Woodland Avenue.
Authorities say two men got into an argument with two other males for an unknown reason.
During the incident, at least one of the men pulled out a knife and began stabbing two others.
A man in his 40s was stabbed multiple times in the chest and stomach. A man in his 20s was stabbed in the back and shoulder.
Both men were taken to the Hospital of the University of Pennsylvania in critical condition.
No word on any suspects or what sparked the argument.
