The young man has been named locally as 21-year-old Bradley Beck.
It is understood Police, fire service, ambulance personnel, and the charity Air Ambulance attended after a report of a sudden death of a man in his 20s, in the Gobbins Road area of Islandmagee, shortly before 12.25pm.
The death is not being treated as suspicious.
Police have advised the Health and Safety Executive and will provide assistance with their investigation.
A spokesperson for the Health and Safety Executive said: “HSENI are making enquiries into an incident which took place in the Islandmagee area earlier today.
“We are working to establish the facts surrounding the incident.”
A NIAS spokesperson further said: “The Northern Ireland Ambulance Service received a 999 call at 12:16 on Wednesday 15 September following reports of an incident on the Gobbins Road area, Larne.
“NIAS despatched the Charity Air Ambulance and two Rapid Response paramedics to the incident. No one was taken from the scene.”