The present invention aims to provide a disposable pants-type diaper preventing the diapers skin in the vicinity of external genital and/or in the vicinity of anus from being soiled with body waste. A crotch region (6) of a disposable pants-type diaper (1) includes a bodily fluid absorbent structure (45) comprising a liquid-pervious inner sheet, a liquid-impervious outer sheet and a bodily fluid absorbent core and, in addition, a body waste retaining space (31) formed by the inner sheet and the innermost sheet member (120) interposed between the inner sheet and the diaper wearers skin. Segments (33c, 34c) of the innermost sheet member (120) defining peripheral edges (33b, 34b) of a front opening (33) and a rear opening (34) face to each other in a front-back direction (A) and are bonded to each other via two spacers (71, 71) spaced from each other in a transverse direction (B) to form a space (50). A portion of the innermost sheet member (120) extending between the segments (33c, 34c) sags toward the lowermost portion (6a) of the crotch region (6) to form a separator (20a).