Build orientation (BO) is the spacial arrangement of an object with respect to the build plate of the additive manufacturing (AM) machine. Many researchers have shown that BO has significant influence on the properties of the printed part. In this work, we study the effect of BO on the structural properties of the fused filament fabrication (FFF) part. First, we characterize the anisotropy in the part using orthotropic material model. Tensile tests were carried out to extract the elastic constants. An FE analysis is performed using the part model and the extracted elastic constants. Then, we perform an optimization to find the BO corresponding to minimum structural compliance. The results show that there is significant reduction in compliance of the structure. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.