A stent delivery system includes a guide catheter, a stent into which the guide catheter can be inserted, and a pusher catheter into which the guide catheter can be inserted and disposed in a proximal end side relative to the stent. The guide catheter has a guide catheter tip portion protruding to a distal end side further than the stent when the guide catheter is inserted into the stern and the pusher catheter, and a guide catheter body disposed at least partially in the passages of the stent and the pusher catheter. The stent has flexural rigidity equal to or lower than that of the guide catheter body, and the stent mounted region has flexural rigidity equal to or lower than that of the pusher mounted region.
