To increase the color spectra, two kinds of vegetable dyes of natural indigo and brazilwood were selected for the complex dyeing of Antheraea pernyi (A. pernyi) silk fabric. Based on the structures of the two vegetable dyes, the mechanism of molecule reaction and the principle of the complex dyeing were analysized. The dyeing process was performed on the silk samples with natural indigo before brazilwood, and the optimum dyeing technique was determined by single factor. Based on K/S (color strength), a and b values (index for color style), the effects of the amount of brazilwood, pH value and temperature on the index for color style were discussed. The results showed that the dyeing shade was affected greatly by the concentration of brazilwood, and a series colors including green and grey could be obtained by the dyeing process. It was also found that the complex dyeing process provided A. pernyi silk fabric with the similar rubbing fastness and washing fastness of more than 3 or equal 3.