This invention relates to a dental handpiece including turbine blades to be driven by a high-speed fluid under pressure to a turbine rotor chucking a cutting shaft, and blades are provided with openings or cutout portions located at both outside ends in a thrust direction of the blades so as to provide flange portions between the openings and the end portions of the blades and the peripheral width of the blades is larger than that of the high-speed fluid supply apperture.