Maxwell Place Park was temporarily closed on Thursday morning during the investigation but reopened by noon.
The Hudson County Prosecutor's Office is working with police to figure out if the death is suspicious and the Medical Examiner will determine how the man died.
People who live nearby say it was a resident who came out in the morning and discovered the person on the grass and then called for help.
Soon it drew the attention of people like Tom Harkins, who lives across the street.
"I just came outside to see what was going on, I still didn't know, but everything was taped off," Harkins said. "I really wasn't sure what was happening with it, obviously wasn't good and I noticed a very large police presence from what I usually see in Hoboken."
The park is usually filled with people and the path along the Hudson is popular with runners and cyclists all throughout the day.
Residents say whatever the cause, it's troubling to hear it happened in such an active area.
"If it's foul play it would really upsetting and surprising and surprising, but if it was a drug overdose of something like that, then that's just sad," Hoboken resident Ronald Fiorina said.
The investigation into what exactly happened is still ongoing.
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