A detector for wet diaper is suitable for large-scale production. The detector comprises a nonwoven fabric (1) and at least two electrodes (2, 3) which are carbon powder coated on the nonwoven fabric (1). The length of the electrodes (2, 3) is 2-20 mm while the length thereof is more than 3 times than that of the width. The carbon powder is adaptable to the skin of the infants, the old, and the patients. It will not cause allergy or oppression to the skin. Further, the carbon layer possesses the function of filtration and odor adsorption, which is conducive to the hygiene and health of the subjects, such as, the infant, the old and the patients.
