In this research, polypropylene (PP) fabrics were modified with two types of ionic liquids, 1-ethyl-2,3-dimethylimidazolium ethyl sulfate (EIL) (2, 6, 10 wt%/v in ethanol) and methyl-tri-n-butylammonium methyl sulfate (10, 15, 20 wt%/v in ethanol) at different concentrations. PP fabrics were pre-treated with chromic acid solutions for improving surface functionalization. The pre-treatment led to increases in moisture content, hydrogen bonding related absorption peaks and surface roughness of the PP. The pre-treatment changed surface resistivity from 7.1 x 10(10) to 4.1 x 10(13) ohm/sq. With the given set up, surface resistivities of the PP decreased with the ionic liquids for short - and long-term periods. Increasing the concentration of the ionic liquids can be considered as an efficient way to reduce the surface resistivity of PP. Thermal conductivity of the PP rose up significantly after BIL and EIL modification of PP. Crystalline structure and thermal stability of the PP altered after modification of PP. It was observed that a coating layer formed on surface of the fabric and in the gaps of the yarns of PP with modification. This cost-effective and environmentally-friendly method can be used as an alternative way for improving conductivity of PP fabrics generally characterized by their high surface resistivity.