In wrapping a blood pressure measurement cuff enclosing therein a bladder, which is inflated when supplied with air, around a region for measurement, first, a predetermined amount of air is supplied to the bladder and then enclosed therein. Then, the blood pressure measurement cuff is wrapped around the region for measurement of a subject for the purpose of measuring his/her blood pressure. During this wrapping process, relative variations in the pressure in the bladder are sequentially detected. The time period in which the detection results indicate that the variation has not reached a predetermined threshold value, the wrapping proceeds. When the detection results indicate that the variation has reached the predetermined threshold value, the wrapping is terminated.