[Problem] To provide a method of manufacturing a stent delivery system and a stent delivery system that can reduce an insertion resistance of an outer pipe relative to an inner wall surface of another medical appliance, such as a catheter.[Means for Resolution] The method of manufacturing a stent delivery system that includes: an inner pipe 20, a first outer pipe 41 and a second outer pipe 42 that are capable of relatively moving forward and rearward relative to the inner pipe, a stent 30 disposed between the inner pipe and the first and second outer pipes, and a pair of operation wires 50a and 50b that operates the forward and rearward movement of the first outer pipe and the second outer pipe, includes: a step of preparing an inner-side tube 300 and an outer-side tube 400 that form the first outer pipe and the second outer pipe； a step of deforming, by disposing an insertion member 200 in a lumen of the inner-side tube 300, opposing two locations of the inner-side tube so as to be brought closer to each other inwardly in a radial direction of the inner-side tube 300； a step of disposing the respective operation wires in the pair on outer peripheral sides of the opposing two locations of the inner-side tube； a step of disposing the outer-side tube at an outer peripheral side of the inner-side tube so as to surround the inner-side tube and the pair of the operation wires； and a step of disposing, in a state where an insertion member is disposed in the lumen of the inner-side tube, a retaining member 41g that retains a cross-sectional shape of the inner-side tube in a space 303 formed between the inner-side tube and the outer-side tube.
