PROBLEM TO BE SOLVED: To provide a pants-type disposable diaper having side seal parts formed at both left/right sides of the diaper and having favorable external appearance, and having excellent texture in the side seal parts.SOLUTION: The pants-type disposable diaper includes a pair of side seal parts 4 formed thereon, where each of the pair of side seal parts 4 includes a main joining area 40 extending in the vertical direction, and a sub joining area 50 located horizontally outward the main joining area 40 and extending in the vertical direction. A joining area ratio of a plurality of sub embossment parts 51 in the sub joining area 50 is smaller than a joining area ratio of a plurality of main embossment parts 41 in the main joining area 40, and consequently, joining strength of the sub joining area 50 is set weaker than the joining strength of the main joining area 40.
