Hornqvist scored with 6:22 remaining and Dan Ellis stopped all 22 shots he faced for his first shutout of the season and the 10th of his career as the Predators won 1-0 at the Pengrowth Saddledome and jumped three points ahead of the Flames for fourth place in the Western Conference.
It was the 12th time in Predators history they won a 1-0 game. It also completed a three-game sweep through western Canada, following victories over the Canucks and Oilers.
"Our 'D' did an exceptional job tonight," Ellis said. "They kept everything to the outside. They took away their dangerous players in (Olli) Jokinen and (Jarome) Iginla, and they didn't give them very many opportunities."
Miikka Kiprusoff turned aside 20 shots for the Flames, who entered the night with an identical record to the Colorado Avalanche and missed an opportunity to move into sole possession of first place in the Northwest Division.
"We've got the defensive side of the game going very well, we're getting great goaltending, guys are blocking a lot of shots and getting the shots down," Iginla said.
"It's no secret we need to score goals. It's obviously a tough drought, but you've got to stay positive. Keep believing it's going to go the next shift, the next game and it will."
Hornqvist, who scored twice in 28 games last season as a rookie, picked up his 19th of the season when he beat Kiprusoff after Steve Sullivan passed from behind the net. Hornqvist has 13 goals in his last 18 games dating back to Dec. 8.
"Everything's going right for me," Hornqvist said. "It wasn't really even a good opportunity to score, but Sully made a good pass and it went in. I'm getting lots of good bounces right now. I've got to keep going in front of the net and work hard every night and hopefully get good bounces next game too."
Both goalies were tested over the first 40 minutes and came up strong. Kiprusoff denied J.P. Dumont from the slot in the first period with a glove save and used his blocker to turn aside a one-timer by David Legwand in the second.
"He made some incredible saves, especially early in the game," Ellis said of his goaltending counterpart. "He was a rock for them like he has been all year."
Ellis made a nice save of his own when David Moss sent a pass from behind the net to Olli Jokinen in the slot, kicking the puck away late in the first to keep the game scoreless. Ellis proved to be lucky as well as good, as Jokinen also rang a shot off the post in the third.
"He found the tiny little part that was open and fortunately he hit the outside of the post instead of the inside," Ellis said.
Material from wire services and team broadcast media was used in this report.