The incident occurred around 9 p.m. during a performance of Dead & Company. The Post reports that the man fell between "30 and 50 feet" before landing on concrete.
"Upon arrival, officers observed EMS personnel attending to a 46-year-old male who was suffering from injuries consistent with a fall from an elevated position," Detective Sophia Mason, a spokeswoman for the NYPD, told CNN in a statement.
After EMS arrived on the scene, the man was transported to Queen's New York-Presbyterian Hospital, where he was pronounced dead.
The man's identity has not been released, though the Post and the Daily News report he was in his 40s.
"We are aware of a tragic incident which sadly resulted in a fatality last night," New York Mets spokesperson Harold Kaufman told CNN. "Our deepest and heartfelt condolences go out to the attendee's loved ones."
Dead & Company, an offshoot of the legendary rock band Grateful Dead, includes three original group members and guitarist John Mayer and other musicians. The group recently made headlines by requiring proof of vaccination to attend shows.