Abstract: The axial cross-sectional profile of the grinding wheel for machining spiral surface using five-axis NC machine tool is generally consisted of many arcs and line segments.It is difficult to solve this problem.According to traditional approach, the contacting equation in the process of solving the complicated axial cross-sectional profile of the cutter is an implicit one, which can not be solved analytically.The authors make the continuous problem discrete and give the iterative solution and fitted to the solution, finally, the solution is output and equation solution and graph solution are optimized.Experimental results show that the approach can meet the high-accuracy requirements and efficiency requirements.