A rain sensor is included in a vehicle, and a method for controlling the vehicle utilizes the rain sensor. The rain sensor includes a light transmitter configured to radiate light to a windshield of the vehicle; a light receiver configured to receive light reflected from the windshield to generate a reception light signal; a filter configured to filter out noise from the reception light signal; and a controller configured to determine a presence or absence of pollutant and a degree of pollution on the basis of the filtered reception light signal, and perform pollutant removing.