A stent delivery system (1) is provided with a self-expandable stent (10), a shaft section (3) having a guide wire lumen (61), and a sheath (2) having the stent (10) contained in a distal portion thereof. The stent (10) is located at a position which is on the shaft section (3) and near the distal end of the shaft section (3). The stent delivery system (1) has a stent proximal portion fixing wire (5) and a breaking member (7). The stent proximal portion fixing wire (5) has one end portion (5a) and the other end portion (5b) which are fixed to the shaft section (3), and also has an intermediate portion (5c) engaged with a proximal portion of the stent (10) The breaking member (7) breaks the stent proximal portion fixing wire (5) to release the stent from the engagement.
