This treatment device for endoscope is used for cutting body tissue while the treatment device is retractably projected from a catheter. The treatment device includes: a control wire inserted into the catheter and a cutting electrode mounted at the distal end of the control wire with the cutting electrode being imparted a bent configuration in advance. The cutting electrode elastically deforms in a state where the cutting electrode is retracted into the catheter, thereby assuming such a shape as to resemble the configuration of the catheter.
