The man, whose name has not yet been released, was on a speedflyer wing - equipment designed for high-speed flying close to the ground - and was a private flying enthusiast, not part of a commercial operation.
He had launched in windy conditions from the Treble Cone skifield access road at a point about 820m above sea level before crashing shortly after midday about 200m below the road, and sustaining "significant impact injuries", Land Search and Rescue (LandSAR) spokesman Phil Melchior said.
Several paraglider pilots flying in the area at the time, some who were friends of the man, saw the crash.
"The other flyers ... went to the site, raised the alarm and tried to resuscitate him for about 40 minutes, but were unsuccessful," Mr Melchior said.
"He was unconscious when he was found and did not regain consciousness."
Wanaka ambulance officer Don MacMillan confirmed the man was dead when St John staff arrived.
Three LandSAR Alpine Cliff Rescue team members also attended the accident.
Wanaka adventurer and speedflying enthusiast Mal Haskins, who is also a member of the New Zealand Hang Gliding and Paragliding Association, said the man was an experienced skydiver and base jumper, had recently completed a paragliding course, and had been speedflying for about two years.
He was based in Wanaka while also spending time working overseas for the past year, and was well known in New Zealand's speedflying community.
Speedflying was a high-risk activity and still a "relatively new and fringe sport" in New Zealand, Mr Haskins said.
The man's body was removed from the crash site about two hours after the accident and taken to the medical centre. His death has been referred to the coroner. Police would release his name once next of kin had been advised.
Mr Haskins described speedflying as a combination of paragliding and skydiving.
Unlike paragliders, which were designed for soaring flight, speedfly wings were designed to descend, Mr Haskins said.
"It involves high speed and proximity to the ground, so it involves a lot of skill ... and not much room for error."
The sport evolved from speedriding, which involves launching from a mountain and flying and skiing down, using a specialised wing, at speeds of up to 100kmh. In the absence of snow, foot-launched speedflying was developed, with pilots travelling close to the terrain at high speed.
