Abstract: A new kind of porous composite used as bone and cartilage tissue engineering scaffolds was prepared with chitosan，gelatin and 3-aminopropyltriethoxysilane modified bioglass (SBG) by the freeze-drying technique in order to improve the compatibility of BG and polymer. The porosity，bending strength and microstructure of the composite scaffolds were characterized. The effects of the concent ration of SBG and CS-Gel，the cross linking agent and the super-cooling temperature on the microstructure of the composite scaffolds were investigated，respectively. The results show that the composite scaffolds with 3D interconnective porous structure，high porosity (90%) and high mechanical strength could be prepared under 70 g·L^-1 of SBG concentration and 40 g· L^-1 of CS-Gel concentration，then crosslinked with EDC and NHS，frozen at -50℃ for 2h and -15℃ for 15h，and finally lyophilized.