Carbon nanotube (CNT) / carbon fiber (CF) composite was prepared by growing CNT in situ on the CF surface with catalytic chemical vapor deposition. The morphology of the obtained composite was characterized by the scanning electron microscopy. The results show that the CNT is trimly and equably grown on the CF surface. The obtained CNT/CF composite is covered with a layer of nickel (Ni) as a current collection on one side of the composite through the spray method. Then, the obtained materials were assembled to electrochemical super capacitors to characterize their electrochemical performances. The results show that the specific capacitance of the composite could be up to 105.4 F•g-1 (organic electrolyte), which is much higher than those of the pure CNT and the CF (about 25.0 and 62.2F•g-1, respectively). These experimental results show that CNT grown in situ on the CF surface is a simple and feasible method to enhance the composite electrochemical performances.