 This paper presents an automatic determination method for part-build orientation in laser-powder bed fusion that involves two steps, generating alternative orientations using a facet clustering-based approach and estimating the values of support volume, volumetric error, surface roughness, build time, and build cost for each alternative orientation using certain estimation models. The weights of these factors are determined via pair-wise comparison, and a weighted sum model is used to calculate a summary value for each alternative orientation. An optimal orientation is generated based on the calculated summary values, and the methods effectiveness and efficiency are demonstrated through testing with a set of part-orientation cases. This article was authored by Yu-Chu-Ching, Chu-In-Fan-Chi, Pei-Zhisha, and others.