To obtain a water wetting detecting label capable of easily discriminating the cause for the trouble occurring in the water wetting of mobile and portable precision electronic apparatus, etc.

This label has at least a base material 4 and a water wetting layer 5 disposed on this base material 4 and may be provided with a water permeable protective layer 9 and a display layer on the water wetting layer 5 on the base material 4 and may have a tacky adhesive layer 3 on the other side on the side having the water wetting layer 5 of the base material 4. The base material 4 is transparent, has the tacky adhesive layer 3 on the water wetting layer 5 on the base material 4 and may consist of the constitution subjected to a perforation treatment. The constitution respectively partially provided with the water wetting layer 5 and the tacky adhesive layer 3 having the thickness larger than the thickness of this layer on the base material 4 is equally preferable. The label has the protective layer 9 subjected to the perforation treatment on the water wetting layer 5 on the base material 4 and the water wetting layer 5 is printed with characters or images. Also, the constitution having the tacky adhesive layer 3 on another side of the base material is equally preferable.