In order to produce the colored cocoons we finalized the adequate amount of dyes throughout several trial and error experiments. The proper amount of each dye required for per 100 g of each colored cocoon turned out to be 150 mg of Rhodamine, 1560 mg of Thionin, 170 mg of Neutral red, and 200 mg of N-Blue, respectively. With this amount of dyes silkworms grew without physiological disorders. In order to produce colored cocoons, artificial diet composed mainly of mulberry leaves was fed to silkworms from the beginning of 5th instar, and subsequently fed with dye included diet from 4th day of the 5th instar. This process resultantly produced colored silkworm body from the onset of feeding and subsequently colored cocoons and eggs. Nevertheless, the dye induced color was not inherited to next generation.