Abstract: In this paper, carbon nanotubes were utilized to modify silk. The optimum process conditions, characterized by volume resistivity, were discussed through single factor experiment and orthogonal test, and the properties of modified silk were investigated. It showed that the optimum process conditions were as follows: the pH value 3.0, the bath ratio 1:500, carbon nanotube mass fraction 0.07%, reacting at 70℃ for 90 min, the silk’s electric conductivity improved a lot after treated, and it’s volume resistivity was 0.00715Ω·cm under the optimum conditions; The verification of durability indicated that, it has better durability; The SEM image showed that, there were granular conductive material uniformly on the surface of the silk; and infrared spectrum analysis showed that Alpha-helix structure and Beta-sheet structure of conductive silk increased; The breaking strength and breaking elongation of the conductive silk were descended a little, which didn’t influence the wearability of the conductive fabric; The X-ray diffraction analysis showed that the degree of crystallization of conductive silk descended a little; TG analysis showed that the conductive silk’s thermal stability did not change obviously.