In this paper, calcium sulfate hemihydrate (CSH) was added into silk fibroin/calcium phosphate (SF/CP) composites. The macropores formed by the SF was connected by micropores formed from rapid degradation of CSH, so that the structure of the composites is more close to the natural bone. The results indicated that the range of pore sizes around 30 - 308 microns were formed in the composites by SF. Compared to SF/CP composites without CSH, the injectability decreased, but the rate were both above 90%; the setting time increased, but were both less than 16min; the porosity increased. When the proportion of CSH was greater than 10%, the morphology of the product of setting reaction, i.e. the hydroxyapatite (HA) crystals, was influenced. When the proportion of CSH was less than 10%, the HA crystals appeared to be needle-like and plate-like crystals. When the proportion of CSH was greater than 10%, HA crystals were needle-like. The added amount of CSH had significant effects on compressive strength and work-of-compressive. The compressive strength and work-of-compressive decreased with increasing of CSH content in the composites.