In this experiment,cross-linked waxy corn starch were prepared with waxy corn starch as raw material,with epichlorohydrin as cross-linking agent under alkaline conditions using chemically modified method.Quadratic regression orthogonal combination experiments design was applied with cross-linking degree as test indexes,then the data were analyzed by regression and ANOVA based on above-mentioned experimental results and variance analysis to obtain the optimal preparation conditions,i.e.,dosage of sodium hydroxide X₁= 0.872 g,dosage of epoxy chloropropane X₂= 0.5 mL,reaction temperature X₃= 53.6℃,the reaction time X₄ = 2.64 h.Optimal regression equations were established,and verification experiments were carried out.