Police responded to Martin Ray Reilly Park on Chestnut and Turner Avenues at midnight for a welfare check on an adult who was reported bleeding.
Officers found a man injured with multiple stab wounds in the upper body.
Medical aid was provided, and the man was taken to a nearby hospital but died from his injuries.
Police blocked off the area for several hours and interviewed witnesses.
There is no suspect information at this time.
If you have any information, you can call the Fresno Police Department.