Emergency crews responded to the park near 90th Street and West Drive just after 1 p.m.
An Eyewitness News crew saw rescuers pull the person from the reservoir, and a police helicopter was also flying overhead.
He was taken to St Luke's Hospital, where he was pronounced dead.
Several people posted video and photos to social media showing the activity:
@andrewsiff4NY Central Park/93th St, now! pic.twitter.com/CFFbwya6Xb
— Juan Carlos (@juan902carlos) September 22, 2015
Something going down in #CentralPark reservoir. NYPD copter above, at least one diver into water. Multiple 🚑🚒🚓s pic.twitter.com/BXmqYAuKgg
— Nick McCarvel (@NickMcCarvel) September 22, 2015
Lots of #fdny and police in #centralpark near reservoir and W90. Why? pic.twitter.com/I6mcimMCtL
— SkunksMonkey (@SkunksMonkey) September 22, 2015
It is unclear how the person ended up in the water, but at this point, it is being investigated as a suicide after several witnesses reported the man jumped.