Starting fourth on the grid, Motorsport's Verschoor moved up to second on lap 1, and took the lead from pole-sitter Juri Vips on lap 7 as the field returned to racing speed following a safety car period to clear Ferdinand Habsburg's stricken ART.
Vips tried several times to retake the lead as the leading duo approached the Lisboa Bend right-hander, but the delayed deployment of the DRS system meant the Estonian was unable to take advantage of higher speeds on the Guia Circuit's long straights, reported Xinhua news agency.
The Estonian came closest to passing Verschoor on lap 11, but ran wide after he drew alongside and locked his tyres under heavy braking, with the resultant flat spots affecting his car's handling thereafter.
Verschoor's win was all the more impressive considering he had finished a lowly 13th in this season's FIA Formula 3 championship, and unlike many of his rivals, the Dutchman was also racing at Macao for the first time.
"I touched the wall at one point so I was racing the last few laps with a bent steering wheel," explained Verschoor afterwards. "This is the best race ever. It's my favorite track and I can't wait to come back next year. Driving on this track and racing with others is amazing."
After a flawless weekend so far, in which he had qualified on pole for and finished first in Saturday's qualification race, Vips rued his inability to close out the win on Sunday.
"It's disappointing because it had been the perfect weekend up to this point," lamented the Estonian. "I went for the move and locked my tyres, so that was my race done. I couldn't get close enough to attack for victory. Richard deserved the win. He did a fantastic job and took his opportunities."
Behind the top two, American Logan Sargeant was impressive in finishing third from sixth on the grid, and other noteworthy drives came from the New Zealand pair of Liam Lawson and Marcus Armstrong, who finished seventh and eighth respectively after starting 20th and 17th.
2017 and 2018 Macao Grand Prix winner Dan Ticktum failed to make it a hat-trick of wins at Guia after finishing only 13th, though the Briton did well to come through from 26th on the grid after a problematic weekend.
However, it was a hugely disappointing afternoon for Robert Shwartzman. Qualifying second behind Vips, the runaway 2019 Formula 3 champion had been expected to fight for victory in Macao, but the Russian's race was over on lap 1 after contact from Christian Lundgaard punctured his tyre and damaged his front wing.
German racer Sophia Florsch, who survived a horrific crash at last year's Macao Grand Prix, was another driver who failed to see the chequered flag, retiring with an apparent mechanical issue on lap 8.
( With inputs from IANS )