Abstract: Carbon nanotube is a promising enhancemental material for its high strength and excellent toughness. After electroless plating, the carbon nanotube was coated with a relatively continuous and uniform layer of nickel(20 nm~40nm). It was shown by TEM images that nickel was deposited as nanoparticles on the activated sites at the pretreated surface of carbon nanotubes. When the reaction time was prolonged, the nickel layer would become thicker and joined together to form a continuous one. It is not the curvature of MWNTs but the dispersion of catalytic centers on pretreated MWNTs that plays a crucial part in electroless plating.