Abstract: In order to develop an advanced feature which is opened and the grinding path can be freely designed by user in tool grinding system, we developed a free grinding path planning function, the function uses odd matrix and odd transformation to get the position and orientation of the wheel in 3 dimension, through the post-processing module, it is transformed into the machine tool coordinate system to realize freely editing grinding path by user and parametric modification to manufacture standards, non - standard tools and other complex tools.