Police say it happened at 1:30 p.m. on Fayette Street during some sort of fight.
The stabbing occurred just after fans were exiting the M&T Bank Stadium for the Super Bowl Champions, The Baltimore Ravens. They say at that point the parade had already concluded.
Police say the victim, a 15 to 16-year-old male, died after he was taken to Johns Hopkins Hospital.
The two other individuals are said to be around the same age. Police say one is in critical condition and the other is listed in serious condition.
They say the victim was found with no identification and they're still looking into his name.
Police say at this point during the investigation it's not clear if the stabbing was related to the Super Bowl celebration.