Pittsburgh's point total, largest in the Eastern Conference, grew to 72 with Marc-Andre Fleury making 23 saves to get the easy win.
Jokinen opened the scoring midway through the first period and his goal early in the second gave Pittsburgh a 3-1 lead. Sidney Crosby and Evgeni Malkin added second-period goals to turn the game into a blowout.
It was Pittsburgh's third win in four games.
The lone Montreal goal came from Rene Bourque with 2:20 to go in the first period.
Montreal has lost each of its last five games in Pittsburgh.