The aim of this work is to find out the influence of nano BN (Boron Nitride) filler and fabrication technique on the mechanical properties of filler filled polyester composites. Nano BN filled polyester based homogeneous nanocomposites (HNC) and their functionally graded materials (FGMs) are fabricated using stirring and centrifugal casting technique, respectively. HNCs and FGMs are fabricated with the reinforcement of 5 wt% and 10 wt% of nano BN fillers respectively. Unfilled polyester is also fabricated for the performance compression with HNC and FGMs. Result finding shows that hardness of nano BN filled FGMs in higher as compared to HNCs and unfilled polyester. Hardness increases with increase in the amount of nano BN filler for FGMs as well as HNCs. Same trend is also observed for flexural and compressive strength. However tensile strength increase with the addition of 5 wt% of nano BN filler and further decreases with 10 wt% for both, FGMs and HNCs.