The present invention provides a pull-on diaper adapted to be easily put on without stressing legs of a younger baby spread in an M-shape. A pull-on diaper (10) in which respective lateral portions of front and rear waist panels (18, 19) disposed with waist elastics are coupled with each other along seam regions (20) wherein outer end portions (18a, 19a) of the front and rear waist panels (18, 19) define a waist-opening periphery (22) and inner end portions (18b, 19b) of the front and rear waist panels cooperate with lateral portions (13c, 13d) of a crotch panel (13) to define a pair of leg-opening peripheries (23). A distance dimension (L1) between the outer end portions of the front and rear waist panels is in a range of 300 mm to 400 mm as measured on the diaper flatly developed after coupling of the front and rear waist panels in the seam regions has been released. A distance dimension (L2) between the waist elastic closest to the inner end portion of the front waist panel among the waist elastics extending in the front waist panel across the respective seam regions in the front waist panel and the waist elastic closest to the inner end portion of the rear waist panel among the waist elastics extending in the rear waist panel across the respective seam regions is at least 55 % of the distance dimension between the respective outer end portions of the front and rear waist panels.
