To prevent erroneous display of snow cover weight caused when internal pressure of a sealed vessel hourly changes by a temperature characteristic of a pressure sensor and an air temperature by holding weight display in zero when judged that a snow cover does not exist, or using the signal voltage just before reaching the existence of a snow cover from the nonexistence of a snow cover as reference voltage when judged that a snow cover exists, and measuring the weight.

A snow cover gravimeter is provided with a temperature detecting circuit 8 to discriminate the existence of a snow cover on a sealed vessel 1 by a temperature and a weight correcting circuit 11 which hourly changes reference voltage REF so as to approach the signal voltage SIG when judged that a snow cover does not exist by the temperature detecting circuit and stores signal voltage just before reaching the existence of a snow cover from the nonexistence of a snow cover when judged that a snow cover exists and uses the signal voltage as the reference voltage.