He was flung into barriers, losing his helmet and sustaining fatal injuries.
However, a statement issued by the race organizer confirmed that he died en route to the hospital.
"Daniel's family have been contacted, and the committee will ensure every assistance is extended to them", race organisers said in a statement.
Hegarty, from Nottingham, who was a regular at the Isle of Man TT, had tweeted on Friday: 'Positive Q2 jumped from 19th to 15th with much more competitive times.
He was taking part in his second Macau Grand Prix after finishing 16th a year ago.
Hegarty was taking part in his second Macau Grand Prix after finishing 16th past year.More news: Rupee Cheers Moody's Upgrade With Mid-Day Surge
Hegarty had told Bikesportnews.com previous year that he had turned to the road events because that style of racing "didn't hurt my elbow so much".
This is the second deadly accident at the Macau GP since 2012, after Luis Carreira of Portugal died on the same turn.
Irwin, riding a PBM Ducati, had started from pole position but encountered mechanical problems in the early stages of the race.
Carrick rider Glenn Irwin has taken his maiden Macau victory on Saturday in a race that was stopped due to a fatality.
"It's a tragic end to the day - that's not even a podium, we stood on a box with three steps", Irwin said.