The micro crowled integral impeller is one of the key parts of aeroengine. It is difficult to machine for its complex structure and small dimension. In this paper, the tool path planning scheme of micro crowled integral impeller is researched, which lays foundation for the numerical control machining of the part. To begin with, considering the feature of impeller’s structure, a kind of processing route is proposed and the processing regions are divided, which satisfy the demand of accuracy and efficiency. Then, the tool path planning scheme of the impeller is put forward, which is regular and is more suitable for a large-diameter tool to fulfill the machining process. Finally, machining simulation is carried out to prove the feasibility and correctness of the proposed path planning scheme.