Langer shot a 5-under 67 on Saturday to take the second-round lead at the US$1.6 million Champions Tour event at Vallee du Richelieu.
Langer, who is second to points leader Kenny Perry in the Charles Schwab Cup standings, had a bogey-free round on the challenging Rouville course.
"I hit a lot of fairways today which helps me control my distance with my irons," Langer said. "It's a lot easier from the fairway than from the rough. I putted pretty nicely, too. I had a lot of speed on my putts, gave myself a lot of chances with the putts. I was a bit unlucky on some occasions but overall I was very pleased."
The two-time Masters champion finished with five birdies to move to 6-under 138 through 36 holes after opening with a 71.
"I played pretty good (Friday) but made too many bogeys. I made three bogeys otherwise it would have been a great round as well."
With gusts up to 50 kilometres-per-hour Friday the wind tailed off only slightly for the second round with cool conditions and a bit of rain in the mix.
"There was a little bit of stretch in the middle where it seemed like there were 10 to 15, 20 mile-per-hour (15-30 km/h) winds," Langer said. "Today at the end it felt very similar the last few holes. I probably hit two of the best 6-irons I could ever hit. It was at least a two-club wind."
Perry birdied two of his first five holes but bogeyed the eighth and played par the rest of the way to finish with a 1-under 71 after finishing alone in second on Friday with a 70.
"I made 10 pars starting from 10 through 18 so I really never could get anything going," Perry said. "It was pretty blustery out there, tough conditions. Bernhard played a beautiful round of golf to shoot a 67. I couldn't make it happen today but I'm still in the golf tournament."
Perry is in a five-way tie for second at 3-under 141.
"If he shoots even par and I shoot 4-under I'll win the golf tournament," Perry said. "So he needs to play a good round of golf and I need to play a great round of golf, and if he plays a really good round of golf nobody's going to catch him."
He has 2,619 points to Langer's 1,830 in competition for the Charles Schwab Cup.
"My two wins this year have been from behind so I kind of like being the chaser and not the guy being chased so hopefully we can get out there (Sunday) and get off to a good start and battle him down to the end," Perry said.
"But there are still a lot of guys at 3-under," he added. "One of those guys, if they shoot a great round, they could still win the golf tournament, too. It's not just between me and him. There's probably a handful of players that can win this golf tournament."
Willie Wood and Chien Soon Lu each shot 4-under 68 for a share of second at 3 under through 36 holes along with Perry, Bill Glasson and Anders Forsbrand.
Rocco Mediate was also among the eight golfers to shoot 4 under or better Saturday after Dick Mast's 3-under 69 on Friday was good enough for the outright lead through a blustery first round.
Mediate, who cruised to his second Champions Tour win last weekend in Calgary, shot a 68 to move to 1 under. He shot five birdies but closed out with his only bogey of the day after opening with a 75 on Friday.
Rod Spittle of Niagara Falls, Ont., shot his second straight 72 to remain the top Canadian. He is one of eight players tied for 17th, including Mast, who shot a 75 to fall back into the pack one day after claiming his first outright lead in 165 Champions Tour starts.
Victoria's Jeff Rutledge is 6-over through two rounds after shooting a 74. Marc Girouard of Saint-Sauveur, Que., shot six bogeys and three double-bogeys and finished with an 81 to fall back to 15-over 159.