Air conditioner and control method thereof

The invention discloses an air conditioner and a control method thereof. The air conditioner comprises an outdoor air blower, a detecting device and a controller, wherein the detecting device is used for acquiring the relative humidity of outdoor air. The controller is connected with the outdoor air blower and the detecting device, and used for judging whether the relative humidity of outdoor air is higher than the first preset relative humidity or not before the air conditioner enters a defrosting mode and increasing the rotation speed of the outdoor air blower when the relative humidity of outdoor air is higher than the first preset relative humidity. The air conditioner has the advantages that the frosting speed of the heat exchanger of the outdoor air blower can be delayed, the defrosting frequency of the air conditioner is reduced, and the heating operation time is prolonged, so that the heating continuity of the air conditioner is improved, and the comfort of a user is improved.