Polycarbonate (PC)/graphite nanoplatelet (GNP) nanocomposites were prepared using a facile solution method followed by hot-compaction. The effects of GNP content on electrical properties and electromagnetic interference shielding effectiveness (EMI SE) of the nanocomposites in X-band were studied. A very low percolation threshold of 0.005 vol fraction GNP was achieved. Scanning electron microscopy (SEM) revealed uniform dispersion and three-dimensional network of the GNPs in the matrix. The electrical conductivity of the nanocomposites containing 0.037 vol fraction GNP was about 0.413 S/m. Its EMI SE for 1 mm thick sample was 35 dB, which was further increased to about 47 dB for 2 mm thick sample. An exponential increase in EMI SE was observed with increasing logarithm of electrical conductivity. (C) 2017 Elsevier B.V. All rights reserved.