It's Kingsbury's sixth national championship and the fourth single moguls title overall. Kingsbury won three consecutive titles between 2011-2013 before finishing second to Alex Bilodeau last year.
Kingsbury won the title with a score of 89.91. Marc-Antoine Gagnon of Terrebonne, Que., claimed second place with 87.41 points, and Philippe Marquis of Quebec City finished in third place with 86.84.
"Being a national champion is a great honour and a great title to have," said Kingsbury. "It's been an extraordinary season with a lot of history and this is a nice way to end it. It wasn't the easiest of days. It's a tough course and the conditions weren't the best. I was really pushed by my teammates though who skied great. I'm happy with the final result."
World Cup teammate Simon Pouliot-Cavanagh of Quebec City finished fourth with a score of 84.44.
"You have four guys who are ranked in the top-10 in the world doing their best jumps," said Kingsbury. "None of us wanted to take it easy here. We're all super close friends who encourage each other. Competitions like this get us fired up."
Dufour-Lapointe scored 80.37 to win her second career national championship and her first in single moguls.
"This is a great feeling to have," said Dufour-Lapointe. "It had been a couple of years since I've competed in this event so it's special to win the title today.
"To be able to do this in front of our Canadian fans and our family out here makes it even more special."
Her sisters, Maxime (79.71) and Justine scored (74.92) finished second and fourth, respectively. Audrey Robichaud of Quebec City finished third with 79.27.