Scotty put down scores of 88.25 and 91.25 to breeze into the final where he will be looking to add to the bronze medal he won four years ago.
Ayumu Hirano of Japan was the leading qualifier with a score of 93.25. American superstar Shaun White, competing in his final Olympic campaign, was the fourth best qualifier scoring 86.25.
"It's a beautiful day and I'm really happy with how that all went," Scotty said.
"The best bit was we stuck to our plan and when you do that you are happy with the result.
"My last trick was a frontside 1440 with a tail grab. I'm really happy to [have] put it all together."
Despite reaching the podium four years ago, Scotty isn't putting any pressure on himself ahead of the final on Friday.
"For me, I'd be happy on Friday to come out and execute exactly what my plan is."
Valentino showed nerves of steel to qualify in fifth position with a brilliant second run of 85.74. It was a score he needed to post after a first run of 31.75 that was well below his capabilities.
"On the first run I just made a little mistake which I've never made on that trick, ever," Val said.
"I tend to stay pretty calm, and I did that before the second run. I stepped away, reset [myself] and got myself ready to go. I am happy I stomped it."
Both competitors will have three runs down the halfpipe in the final, with qualification scores not carrying over. The best of each competitors' three scores will determine the medals.
Earlier in the day, PyeongChang 2018 finalist Emily Arthur was unable to advance to the last 12 in the women's competition.
Emily put down a solid first run of 62.50 to see her right on the cusp of the final 12 after the completion of the first round, but heading into her second run, she knew she needed to improve on her score as she had been relegated down to 13th place.
Despite a solid start, Emily was unable to stick one of her landings, crashing out and finishing with a score of 19.75. It saw her place 14th after the completion of two runs.
"It's OK, I'm walking away safely and not injured," Emily said.
"The second run was going really well, until I got there a little bit early, it's rough, I know I'm good enough to make the final but it's all OK.
The men's halfpipe final will be held on Friday 11 February from 12:30pm AEDT.