Electrophoretic deposition (EPD) technique was applied to deposit carbon nanotubes on a carbon fabric. Optimization of EPD conditions was investigated to improve electrical conductivity for CNTs/carbon fiber hybrid multiscale composites by Taguchi method. Based on design of experiment, a L9(3)4 orthogonal array was chosen to conduct experiments. Due to the electrical conductivity of composites increased with the increasing content of CNTs in composites, it was selected as the response on the analysis of the means (ANOM) and the signal to noise (S/N) ratio. In addition, scanning electron microscopy (SEM) was utilized to examine the distribution of CNTs on the surface of a carbon fabric. The statistical software MINITAB 14 was utilized to determine the optimal deposition conditions.