An air conditioner comprising a case defining an outer appearance of an outdoor unit, the case accommodating an outdoor heat exchanger, an outdoor unit fan, and a fan motor for operating the outdoor unit fan therein and a grill configured to prevent foreign substances from being introduced through a discharge hole that is opened in the case, the air conditioner comprising: a snowfall detection device extending upward from one side of the grill configured to detect an amount of snow accumulated on the grill from an upper side of the grill; and a control part operating the fan motor according to a snowfall detection signal inputted from the snowfall detection device to rotate the outdoor unit fan, thereby configured to remove snow accumulated on the grill and the outdoor fan characterized in that the snowfall detection device comprises a distance sensor that is configured to measure a distance between a surface of the snow accumulated on the grill and the snowfall detection device to detect an amount of snow in a non-contact manner, the snowfall detection device comprises: a detection device body fixed and mounted on a top surface of the case extending upward from the grill; a Printed Circuit Board disposed on an upper end of the detection device body and on which a snowfall sensor for detecting the snowfall and an amount of snow is mounted; and a detection device cover coupled to the upper end of the detection device body to provide an accommodating space for accommodating the PCB therein, and wherein preferably the PCB is mounted on an inner top surface of the detection device cover. a snowfall detection device extending upward from one side of the grill configured to detect an amount of snow accumulated on the grill from an upper side of the grill; and a control part operating the fan motor according to a snowfall detection signal inputted from the snowfall detection device to rotate the outdoor unit fan, thereby configured to remove snow accumulated on the grill and the outdoor fan characterized in that the snowfall detection device comprises a distance sensor that is configured to measure a distance between a surface of the snow accumulated on the grill and the snowfall detection device to detect an amount of snow in a non-contact manner, the snowfall detection device comprises: a detection device body fixed and mounted on a top surface of the case extending upward from the grill; a Printed Circuit Board disposed on an upper end of the detection device body and on which a snowfall sensor for detecting the snowfall and an amount of snow is mounted; and a detection device cover coupled to the upper end of the detection device body to provide an accommodating space for accommodating the PCB therein, and wherein preferably the PCB is mounted on an inner top surface of the detection device cover. a detection device body fixed and mounted on a top surface of the case extending upward from the grill; a Printed Circuit Board disposed on an upper end of the detection device body and on which a snowfall sensor for detecting the snowfall and an amount of snow is mounted; and a detection device cover coupled to the upper end of the detection device body to provide an accommodating space for accommodating the PCB therein, and wherein preferably the PCB is mounted on an inner top surface of the detection device cover.