In truth the Australian No.1 did not play at his best, but he did not need to as his opponent, Swiss qualifier Leandro Riedi, made a slew of errors.
De Minaur did, however, show flashes of genius in putting away the world No.435 6-3 6-2 6-1 in 93 minutes.
The last Australian in the adult singles de Minaur thus eased into a third New York quarter-final where he will meet world No.27 Felix Auger-Aliassime who beat Russia's Andrey Rublev 7-5 6-3 6-4 in two hours, 16 minutes.
The pair have met three times prior with Auger-Aliassime having a 2-1 lead including their only previous outdoor hardcourt meeting, in Cincinnati in 2022.
The Canadian will be a far tougher test than Riedi who froze under pressure and played a poor game tactically, feeding de Minaur's brilliant returning by trying in vain to blast the Aussie off court.
Indeed, the only time the Australian looked mildly flustered was when he was asked, in the post-match interview, to demonstrate his command of Spanish to the many Hispanic fans in the crowd, but even then he soon regained his composure
De Minaur's match was first up on Louis Armstrong Court on Monday (local time), with a decent but not full crowd basking in relatively moderate - for New York - 25C sunshine.
The first set turned on three breaks mid-set. De Minaur won two of them, and that gave him control of the match.
In the second set he swiftly moved to 5-0 only to be surprisingly broken. But he served out at the second opportunity.
Any thoughts of a revival by the Swiss were quickly extinguished when de Minaur broke to love in game three of the third set. Riedi had a point to break back but failed to take it and de Minaur broke again, then again, the match ending with his opponent's ninth double-fault.
"I was happy with my level, my focus," said de Minaur. "I knew he had some big shots and he's had a hell of a week coming through quallies.
""I'm super proud of what I'm doing. Ultimately this is where I want to be, playing for the big titles, being in contention. I am putting myself in the right places. I've got another great opportunity coming up in the quarter-finals, I'm gonna go out and have a swing."
