Abstract: Aiming at the part build orientation planning problem in the selective laser melting process, an automatic generation method of selective laser melting part build orientation based on fuzzy information aggregation operators was proposed. First, a set of alternative build orientations of a selective laser melting part was generated using a facet clustering-based generation method. Second, two operators for attribute value aggregation were constructed, and the support volume, volumetric error, surface roughness, build time and build cost in each alternative build orientation were estimated to obtain attribute values. Based on this, a normalized fuzzy decision matrix was established. The fuzzy information in the matrix was aggregated using the constructed operators. According to the aggregation values, a ranking of all alternative build orientations was generate, and the optimal build orientation was determined on the basis of the ranking. A case model illustrates the operability and effectiveness of the proposed method. The experimental analysis gives a set of freeform surface models, and the accuracy of the proposed method is verified by combining the existing methods. The comparative analysis highlights the advantages of the proposed method to capture the relationship between attributes and reduce the influence of extreme values on the aggregation results.