Enjoying a superb run of form, Kyrgios suffered his first loss since falling to Novak Djokovic in the Wimbledon final.
The Australian's run included a title at the Citi Open, before he ran into Hurkacz, who improved his record to 2-0, following a three-set win earlier this year in the Halle semi-finals.
"Nick has been playing really unbelievable throughout the past few months," said Hurkacz. "Battling against him, it's very challenging, but it's also fun.
"He can make every single shot. He doesn't really have that many weaknesses, if any. I was just trying to serve good and stay aggressive."
Hurkacz will next face Norwegian fourth seed Caper Ruud, who strolled into the last four by sweeping aside sixth-seeded hometown favourite Felix Auger-Aliassime 6-1 6-2.
Kyrgios shrugged off the end of his winning streak, saying he did not care and was more interested in getting home after the US Open to see his mother and father, who are not well.
"I honestly don't care," said the Australian, adding that he would head to Cincinnati as soon as possible, where he will continue his build-up to the US Open. "I've been away from home, away from my mum, away from my dad.
"They're not very well at the moment. So I don't really care about 'no winning streak'. I've got two more tournaments left before I can go home," he said, referring to Cincinnati and the U.S. Open.
BIG SERVERS
The two big servers pounded away at each other on Centre Court with Hurkacz blasting 20 aces and Kyrgios hitting back with 19 in a contest that produced two breaks, both going to the Pole in the final set.
What had been a tight contest suddenly turned in the third when Hurkacz, helped by a pair of Kyrgios double faults, secured the first break.
With the help of yet another Kyrgios double-fault Hurkacz broke the Australian again to go 5-1 up and held serve to book his place in the last four.
Flag-waving Canadian fans later filled centre court in the hope of watching Auger-Aliassime make it to the weekend.
He got off to a positive start by breaking Ruud at the first opportunity, but it was all disappointment from there as the misfiring Quebec native committed far more unforced errors.
"It was one of those days where everything goes in one (person's) favour and luckily it was in my favour," said Ruud. "I am sure Felix has played better than he has today.
"It is a pity because he is playing at home. Maybe that was a factor. You could be nervous, but I am not going to talk for Felix."
Briton Dan Evans also advanced to the semi-finals, coming back from a set down to hand American Tommy Paul a 1-6, 6-3, 6-4 loss to set up a last-four meeting with Pablo Carreno-Busta.
The Spaniard won 7-6(4), 6-1 against British qualifier Jack Draper to book his place in the next round.
