Abstract: Aiming at machining for complex curve in 6-coordinate space,a control algorithm is presented in 6-axis simultaneous feeding.Based on moving relationship among the 6 axes,the feed velocity is composited by which the interpolation variable is developed and relative interpolation coordinates for 6 axis are obtained to implement constant-speed control on the moving point.By using the control algorithm,the multi-axis simultaneous feeding interpolation to grind the conical cutter is tested in the 6-axis embedded CNC(computer numeric control) tool grinding system.The interpolation equations are deducted according to the mathematical model of the conical milling cutter.Both the simulation and field test show the interpolation algorithm is feasible with high efficiency to implement the complex curve in 6-axis simultaneous feeding and the resultant speed for feeding can be controlled at constant speed to keep high machining quality.