The invention discloses a continuous reaction dynamic model modeling method for amino acid chlorination and dichloroacetonitrile generation. The method comprises the following steps of S01, establishing an expression for dichloroacetonitrile concentration change along with time according to a fact that aspartic acid generates the dichloroacetonitrile and dichloroacetonitrile hydrolysis accord witha one-stage continuous reaction; S02, performing derivation on a dichloroacetonitrile concentration formula for obtaining a time expression which corresponds with a highest value, introducing the time expression into a dichloroacetonitrile concentration expression in S01, and obtaining the expression for highest dichloroacetonitrile concentration change along with time; and S03, introducing the dichloroacetonitrile concentration and time data of no less than one actual reaction system into the expression of S01, and obtaining the parameter of the expression through MATLAB software nonlinear fitting. The continuous reaction dynamic model modeling method for amino acid chlorination and dichloroacetonitrile generation is used for expressing a change rule of dichloroacetonitrile generation from aspartic acid along with time, and facilitates researching control for generating a nitrogen-containing sterilizing by-product and a processing technique thereof.