An endoscopic treatment system includes: an endoscopic treatment device having an operating unit which has a distal end and a proximal end and a sheath； and a guide wire which has a coated region applied with coating at a distal end. A packaging material has a tray which maintains a predetermined position relationship between the sheath and the guide wire and holds the distal end side of the sheath in a state where the coated region of the guide wire is exposed from the distal end of the sheath. The tray is located on the distal end side of the sheath to a sheath holding portion, which holds the sheath, and has a wire accommodating portion which holds the full length of the coated region of the guide wire exposed from the distal end of the sheath in a linear form.
