As the development of bionic surface engineering technology, many excellent surface properties of micro-texture surface have been confirmed by more and more research, such as drag reduction and wear resistance. But its application and promotion have been limited by complex and inefficient manufacturing techniques. As an efficient and automatic processing method, CNC machining can effectively adapt to the processing of complex shape parts and meet the requirements of high precision. Aiming at the numerical control machining technology of blade micro-texture, a collisionfree tool axis generation method is proposed. The method first obtains a tool path curve by extracting a micro-texture model guide line or intersection line of offset surface of micro-texture surface and smooth blade surface. Then, at each tool point on the tool path curve, a local coordinate system and a reference plane are established according to certain rules. Next, in the reference plane, the oscillating region of the tool axis at the tool point is solved according to the blade interference condition, the machine rotation axis travel and tool parameters. Finally, the collision-free tool axis vector is generated according to the safest principle. Taking an impeller blade as an example, the NXOpen C++ secondary development technology and VERICUT simulation successfully verified the correctness of the collision-free tool axis generation method, and it provides technical support for the high-efficiency CNC machining of the blade micro-texture.