Abstract: A novel method of optimizing the continuous variable constitutive relation of multilayered chiral slab based on genetic algorithm is discussed in this paper. The method derive automatically the continuous variable constitutive relations. The reflection coefficient is calculated by wave-splitting method. Further more, the genetic algorithm is used to search the maximum absorbability of the chiral slab with certain thickness. The one point crossover GA and two points crossover GA have both been tested in the research, the latter one is really more stable than the first one and it's very important to set the proper crossover ration and mutation ration. The advantage of GA would be presented more obviously in designing artificial chiral material model with more variables.