The endoscope treatment system includes an endoscope treatment tool that has an operating section including a distal end and a proximal end, and a sheath that is connected to the distal end of the operating section and is formed with a lumen into which the guide wire is capable of being inserted; a guide wire holder that has a tube member, in which the guide wire is accommodated, and that is circumferentially wound; and a fixing member that couples the operating section to the guide wire holder so that the distal end and the proximal end of the operating section are located outside the circumference of the guide wire holder.