With 15:06 remaining in the first period, Luongo appeared to suffer the injury after kicking out his left leg to make his first and only save of the game against the Penguins. Luongo immediately sprawled to the ice. He was helped off the ice by two teammates and the team trainer to undergo further evaluation.
Curtis Sanford took over in goal.
Luongo is 11-5-2 this season with a League leading five shutouts. He has a 2.18 goals-against average and .928 save percentage.
There was no immediate report on Luongo's status, but a team official said he was being "evaluated" and would not return to the game.
Pavol Demitra scored twice for the Canucks and Daniel and Henrik Sedin had three points as Vancouver picked up it third straight win on the road.
Sanford stopped 17 of 18 shots to earn the win in relief.
Vancouver improved to 7-0-2 in its past nine games and 3-0-1 during a stretch of games in the Central or Eastern time zones. Luongo had been a key contributor during the Canucks' surge, posting a 5-0-2 record with a 0.98 goals-against average in his last seven starts.
Mike Zigomanis scored for the Penguins, and Dany Sabourin stopped 16 of the 18 shots he faced.