A dental handpiece is disclosed which comprises a grip section having a head section in which a treatment tool is detachably attached, and a drive section detachably connected thereto. The grip section comprises a casing having front and rear casing portions, with the front casing portion being continuous to the rear casing portion at an angle a first rotary shaft rotatably supported in the rear casing portion, a cylindrical jacket extending from the head section and arranged and fixed in the front casing portion toward the first rotary shaft, and a second rotary shaft rotatably supported in the jacket, and operatively connected to the treatment tool at one end and to the first rotary shaft at the other end via a gear. The driving force from the drive section is transmitted by means of the first and second rotary shafts to the head section to drive the treatment tool. The jacket is provided with an engagement groove on its circumferential surface. The grip section further comprises engaging means disposed in the rear casing portion and detachably engaging the engagement groove on the jacket, wherein the jacket arranged in the front casing portion is fixed therein by means of engagement of the engagement groove on the jacket and the engaging means in the rear casing portion.
