In this work, the super-hydrophobic coating for multi-walled carbon nanotubes (MWCNT) was treated with a 3:1 trimethylchlorosilane (TMCS)/toluene glow discharge plasma under low pressure and the super-hydrophobic surface of the treated MWCNTs was also investigated. In order to identify the effects of 3:1 TMCS/toluene plasma modification for treatment of MWCNTs powder, an investigation was conducted on the total surface free energies of the MWCNTs powder, which was calculated by measuring the contact angle between the cushion of MWCNTs powder and the probe liquid. The total surface free energies were determined by the Owens-Wendt equation and drastically decreased from 72.90 mJ/m(2) to 0.041 mJ/m(2), respectively. (C) 2010 Elsevier B.V. All rights reserved.