To enable reuse like a cloth diaper, to save labor of the processing person and time of washing and drying, and to improve water retention and comfort of wearing.

This diaper is constructed by sewing lengthwise sides of nonwoven fabrics 111 and 112 so as to form a retaining portion 11, followed by inserting an absorbent 13, in which a sheet material having a layer of highly water absorbing polymer is enclosed, between the both nonwoven fabrics 111 and 112 of the retaining portion 11, and then by inserting the retaining portion 11 into a tubular cover 12. Thus the main body of the diaper can be repeatedly washed and dried following removal of the water absorbent materials after use.