Provincial police Sgt. Bruno Beaulieu said the incident happened on the right-hand side of Highway 35 around 10:15 p.m. local time on Friday.
He said the man suffered critical head injuries after his snowmobile passed under the large animal while it ran across the path.
The snowmobile was barely damaged in the incident.
Two other people who were also on snowmobiles witnessed the incident. Neither of them was injured.
The moose ran off and investigators have not been able to locate it.