Disclosed herein are a turbidity sensor and a control method thereof, and more particularly, to a turbidity sensor capable of measuring turbidity of water including a liquid detergent as well as water including a powdered detergent and a control method thereof. The turbidity sensor includes a first light emitting unit emitting visible light, a first light receiving unit disposed opposite to the first light emitting unit at a position spaced apart from the first light emitting unit and receiving visible light emitted from the first light emitting unit, and a control unit determining a turbidity of a solution according to a ratio between the amount of visible light emitted from the first light emitting unit and the amount of visible light received by the first light receiving unit. According to the turbidity sensor and control method thereof, turbidity of the solution by the first and second particles is accurately measured.