Graft copolymerization technique was selected to improve properties of Bombyx mori silks. The silks were degummed and grafted by 2-hydroxyethyl methacrylate (HEMA), resulting in different graft yields of the degummed silks. It was found that thermal decomposition temperature and wear strength of the silks grafted by HEMA were clearly improved. In addition, dyeing properties of the degummed and HEMA-grafted silks were investigated by using different natural dyes, i.e. coconut shell (Cocos nucifera), pandanus (Pandanus odorus) and Siamese cassia (Cassia siamea) and also synthetic dyestuff, i.e. acid dye. When dyeability and colorfastness properties were investigated, it was observed that higher graft yield of the HEMA-grafted silks exhibited greater dye uptake for all of the applied dyes. Besides, fastness properties to washing, perspiration, light and rubbing of the degummed and HEMA-grafted silks were examined.