Electrically conductive polymer nanocomposites were prepared through selective laser sintering (SLS) of polyamide-12 (PA) powder coated with graphite nanoplatelets (GNP) using sonication. The SLS process parameters were optimized in order to maximize the tensile modulus at 3 and 5 wt% GNP. The highest tensile modulus (2.1 GPa) was achieved at 3 wt%. A slight decrease in flexural modulus and strength was observed at 3 and 5 wt% GNP compared with the neat polymer. Morphological observation of the graphitecoated PA powder showed fairly homogeneous dispersion. The SLS processed parts were nearly fully dense and the highest density (99.5%) was found at 3 wt% GNP. The bulk electrical conductivity of the SLS-processed nanocomposites was found to be $3.8{ imes}10^{-11}$ and $6.4{ imes}10^{-8}$ S/cm for 3 and 5 wt% GNP respectively.