A stent delivery system (S1; S2) for placing a cylindrically-shaped stent at a desired position within a living body, comprising: the cylindrically-shaped stent to be delivered; a guide catheter inserted into the inside of the stent, and which is able to be inserted into the interior of the living body with the stent; a push catheter which can be inserted into the interior of the living body with the guide catheter in a state where the guide catheter is inserted into the inside of the push catheter, and which is for pushing the stent along the guide catheter; a stent connecting member for connecting the stent with the push catheter; and a stent releasing member for releasing the stent from the push catheter by separating the connection between the stent and the push catheter depending on the stent connecting member, which is independently operable without relation to the guide catheter, and which is inserted into the inside of the push catheter, wherein the stent connecting member is a flexible string; one end of the stent connecting member is fixed to the push catheter; the stent connecting member of which the one end is fixed to the push catheter is turned back in a state where the stent connecting member is engaged with the stent through the inside of the push catheter; the other end of the stent connecting member is turned back to reach the inside of the push catheter; and the stent releasing member maintains a state where the stent is connected with the push catheter by holding the other end of the stent connecting member inside of the push catheter, and allows the stent to be separated from the push catheter by releasing the other end of the stent connecting member. the cylindrically-shaped stent to be delivered; a guide catheter inserted into the inside of the stent, and which is able to be inserted into the interior of the living body with the stent; a push catheter which can be inserted into the interior of the living body with the guide catheter in a state where the guide catheter is inserted into the inside of the push catheter, and which is for pushing the stent along the guide catheter; a stent connecting member for connecting the stent with the push catheter; and a stent releasing member for releasing the stent from the push catheter by separating the connection between the stent and the push catheter depending on the stent connecting member, which is independently operable without relation to the guide catheter, and which is inserted into the inside of the push catheter, wherein the stent connecting member is a flexible string; one end of the stent connecting member is fixed to the push catheter; the stent connecting member of which the one end is fixed to the push catheter is turned back in a state where the stent connecting member is engaged with the stent through the inside of the push catheter; the other end of the stent connecting member is turned back to reach the inside of the push catheter; and the stent releasing member maintains a state where the stent is connected with the push catheter by holding the other end of the stent connecting member inside of the push catheter, and allows the stent to be separated from the push catheter by releasing the other end of the stent connecting member.