PURPOSE: To tightly and easily attach/detach a detachable surgical blade to/from a lipped T-shaped locking member extended at a hook-shaped top end part extended along with an opening part in the front end part of a handle and an upper slope with the opening part inbetween while sliding and locking the slot of the blade.

CONSTITUTION: An inclined part 110 of an upper surface 50 is provided for fixing a cutting blade 40 at a front end part 30 consisting of a supporting part for the blade 40 and further, the opening part is provided within the front end part 30 while being extended from an upper edge part 35 inward along with a hook-shape top end part 32. Next, one part of a locking member 70 of the blade 40 is made into T-shaped cross section, and a lip part 100 on its upper end face is provided so as to extend one side to the top end part 32 of the front end part 30 across the said opening part and to extend the other side to the upper surface part 50. Thus, the slot of the cutting blade 40 is engaged with the locking member 70 having the said lip 100, and the inclined part 110 of the upper surface 50 is slid, fixed and held at the suitable part of a rear end part 33 to walls 130.