PURPOSE: To monitor the presence or degree of the incontinence of urine, by detecting the diaper replacing period with the beginning of the incontinence of urine and an increase in the incontinence amount of urine by a sensor and receiving the signal from the sensor to display the same.

CONSTITUTION: The start of the incontinence of urine of a patient wearing a diaper is detected by the first sensor 2 and a diaper replacing period accompanying an increase in the incontinence amount of urine is detected by the second sensor 4. The signals of the first and second sensors 2, 4 are transmitted to a transmitter 7 and received by a receiver 8 to be further discriminated and judged by the discrimination circuit 91 in a control apparatus 9. This discrimination and judge result is displayed and informed by display lamps 101W10n and a buzzer 11 and transmitted to a personal computer 14 to be stored therein.