A human skin moisture measuring device having an interdigitated resistive sensor formed on a plate-like transparent support is described, with a face designed to be placed into contact with the skin to be subjected to the moisture degree measurement. The device further comprises image sensing means turned towards the opposite face of the support and a lighting device arranged sideways relative to the support to direct the light radiation in the support at a prefixed angle. Means for processing the signal coming from the interdigitated resistive sensor and from the image sensing means give as output a value of the measured moisture degree that is normalized with respect to the actual surface of contact between skin and sensor.