Police said the 37-year-old man, from Quebec City region, was on a hiking and skiing trip with a group of people in the Chic-Choc mountains when on Sunday he decided to go off skiing by himself.
But at the end of the day he did return.
Since then about a metre of snow has fallen in the area, which has contributed to the risk of an avalanche.
Avalanche technician Jean-Raphael Lemieux said searchers believe the man could be somewhere on the steep slopes of the Mines Madeleine area.
"We're telling people that they should avoid steep open slopes, because they could definitely trigger an avalanche," Lemieux said.
He said the police crews are all trained in avalanche safety, and he is confident they are taking the proper precautions.
Sgt. Claude Doiron said the man is an experienced outdoorsman and was carrying equipment including a sleeping bag.
Doiron said police are hoping the man found shelter somewhere in the park.