PROBLEM TO BE SOLVED: To provide a manufacturing method of a pants-type wearing article, the method that can easily form a side seal part having high bonding strength.SOLUTION: A manufacturing method of a pants-type wearing article 1 including an outer packaging material having a side seal part, includes: a sealing step of overlapping a continuous assembly of the outer packaging material with elastic members arranged in an extended state between belt-like sheets to overlap at both sides, and then heat sealing a continuous assembly 100 by melting composition fibers of belt-like sheets of the outer packaging material in a state that elastic members are extended in a transport direction at predetermined intervals to form a pair of seal parts and a separation step of separating the pairs of seal parts to form the pants-type wearing article 1. Adhesives are applied to the belt-like sheet of the outer packaging material and/or the elastic members in a heat seal area before the sealing step, and the separating step is performed while the continuous assembly 100 of the outer packaging material is brought into abutment with an anvil block 750 heated to a temperature of melting the composition fiber of the belt-like sheet of the outer packaging material and a pair of seal parts S, S is melted or softened.
