A wind turbine monitoring device for monitoring a wind turbine including a lightning sensor for detecting a lightning strike on a wind turbine blade, comprising: a lightning parameter acquisition part configured to acquire at least one lightning parameter based on an output of the lightning sensor; a lightning level determination part configured to determine a level of the lightning strike based on the at least one lightning parameter acquired by the lightning parameter acquisition part; and an inspection control part configured to judge whether it is necessary to automatically inspect, without any manual operation, the wind turbine blade by at least one inspection unit for inspecting the wind turbine blade, according to the level of the lightning strike determined by the lightning level determination part; wherein the inspection control part is configured to: if the level of the lightning strike is a first level, judge that it is unnecessary to automatically inspect, without any manual operation, the wind turbine blade by the at least one inspection unit; if the level of the lightning strike is a second level more severe than the first level, perform automatic inspection, without any manual operation, of the wind turbine blade by the at least one inspection unit; and if the level of the lightning strike is a third level more severe than the second level, instruct inspection of the wind turbine blade by a different type of inspection unit from the at least one inspection unit. a lightning parameter acquisition part configured to acquire at least one lightning parameter based on an output of the lightning sensor; a lightning level determination part configured to determine a level of the lightning strike based on the at least one lightning parameter acquired by the lightning parameter acquisition part; and an inspection control part configured to judge whether it is necessary to automatically inspect, without any manual operation, the wind turbine blade by at least one inspection unit for inspecting the wind turbine blade, according to the level of the lightning strike determined by the lightning level determination part; wherein the inspection control part is configured to: if the level of the lightning strike is a first level, judge that it is unnecessary to automatically inspect, without any manual operation, the wind turbine blade by the at least one inspection unit; if the level of the lightning strike is a second level more severe than the first level, perform automatic inspection, without any manual operation, of the wind turbine blade by the at least one inspection unit; and if the level of the lightning strike is a third level more severe than the second level, instruct inspection of the wind turbine blade by a different type of inspection unit from the at least one inspection unit. if the level of the lightning strike is a first level, judge that it is unnecessary to automatically inspect, without any manual operation, the wind turbine blade by the at least one inspection unit; if the level of the lightning strike is a second level more severe than the first level, perform automatic inspection, without any manual operation, of the wind turbine blade by the at least one inspection unit; and if the level of the lightning strike is a third level more severe than the second level, instruct inspection of the wind turbine blade by a different type of inspection unit from the at least one inspection unit.