Cleaning device with detection device for humidity detection

The invention relates to a cleaning device (1) for treating a surface to be cleaned by means of a cleaning element (2), said cleaning device (1) having a detection device for detecting the humidity ofthe cleaning element (2), said detection device having a light receiver (3) for receiving reflected light. In order to be able to optimally detect the humidity of the cleaning element (2), it is proposed that the cleaning element (2) is provided with an at least partially light-transmissive element (4) and/or a liquid-absorbing indicator material (5), the light-transmissive element (4) and/or indicator material (5) being designed separately with respect to the cleaning element and contacting the cleaning element (2) in such a way, wherein the cleaning element (2) is arranged in such a way that moisture can be transferred from the cleaning element (2) to the light-transmissive element (4) and/or the indicator material (5), and the detection device is designed to determine the humidity of the cleaning element (2) a