Abstract: ObjectiveThe extraction process of polysaccharides from Lagenaria siceraria(Molina) Standl. were opti-mized by using response surface methodology, in order to provide technical support for further study of polysaccharides from L. siceraria. MethodWith L. siceraria as raw materials, based on single factor experiment, the extraction temper-ature, liquid-solid ratio and extraction time were selected as independent variables. Response surface methodology based on a central composite design with 3 factors and 4 levels was applied to analyze effects of 3 factors and their interactions on extraction rate of polysaccharides , so as to optimize extraction conditions. ResultThe results showed that, the quadratic multinomial regression equation was established as:Y=5.54+0.14A+0.43B+0.36C+0.016AB-0.081AC-0.13BC-0.34A2-0.23B2-0.21C2(R2=0.9956; A: extraction temperature; B: liquid-solid ratio; C: extraction time). The 3 factors af-fecting extraction rate was in order as follows: liquid-solid ratio>extraction time>extraction temperature. Three factors and interaction between liquid-solid ratio and extraction time had extremely significant effect on extraction rate of polysaccha-rides(P<0.01), and the interaction between extraction temperature and extraction time also had significant effect(P<0.05). The optimum extraction process was as follows: extraction temperature of 83 ℃, liquid-solid ratio ratios of 24∶1(mL/g), extraction time of 2.3 h, extracting polysaccharides twice. Under optimum condition, the extraction rate of polysaccharides was up to (5.810±0.240)%, which was close to the theoretical value(5.820%). ConclusionThe response surface method-ology is workable to optimize extraction process of polysaccharides, the optimized process conditions can improve extrac-tion rate of polysaccharides from L. siceraria.