A stent holding member used in a stent delivery system adapted to implant a stent of a cylindrical configuration, designed to be embedded in a living body, to a desired site of implantation in a vessel of the living body. The stent holding member includes a tubular holding member formed of an elastic material. The holder has a groove in its outer peripheral portion for holding one or more supporting struts making up the stent. Each of these supporting struts is embedded at least partially in the groove to hold the stent. The groove has its opening end side expanded by expansion of the holder along the radial direction. By expansion of the opened end of the groove, the stent held in the groove is dilated and released from the holder.