In this article the in situ polymerization of laurolactam in the presence of multiwalled carbon nanotubes (MWCNTs) towards polyamide 12 (PA12)/MWCNT nanocomposite was studied. The processing conditions were optimized with respect to the electrical resistivity and the physical properties. XRD, DSC and ATR analysis were applied in order to investigate the effect of MWCNT of the nanocomposite. Percolation threshold for electrical resistance was occurred at CNT=1.2% which led to 10000 times reduction in the resistivity.