A diamond-containing blade includes a blade body having at proximal end a connection part to be fitted into a gripper; and an edge longitudinally formed along one side of the blade body, wherein the blade is manufactured by a process in which a powder mixture for constituting the edge, including 20 wt % or less of diamond particles coated with Ti and having a particle size of 20 μm or less and residual Ti powder or Ti alloy powder, is charged in a space of a mold corresponding to the edge, Ti powder or Ti alloy powder for constituting the blade body is charged in another space of the mold corresponding to the blade body, the charged powders are pressed to obtain a molded product, the molded product is sintered to obtain a sintered body, and then an edge of the sintered body is sharpened.