Abstract: The resonance frequency and nodal pitch of symmetrical three-step flexural vibration holder have been calculated precisely based on Timoshenko beams theory, and the 3D curved surfaces displaying the variations of the resonance frequency and nodal pitch with the tool holder sizes have been drawn by a computer. It can be from the contour line diagram of these relational surfaces seen that the influence of the length of side beam on the resonance frequency and nodal pitch is larger than the influence of the length of middle beam on that, so a new method to make the nodal pitch of reground tool unchanged by shorting the middle beam has been proposed. The theoretical calculation results show good agreement with the experimental results, the calculating error of resonance frequency and nodal pitch are 3% and 5% , respectively, so that the present method for designing flexural vibration holder is a convenient and accurate method.