For a total change model of a class of biological population: fλ(x)=λsinπx, dynamic analysis of different λvalue in the model is proposed. Firstly, the method classifies the range of λ, then the dynamical properties of fλ(x)are analyzed from two points. Compared with traditional methods, it is more easily applied to different models. Lagrange Mean Value Theorem is applied to the two different branches of the inverse mapping of the model, and the inequality of the inverse mapping about fλis obtained by combining the definitions and properties of the discrete dynamical system, invariant set, repellers and Hausdorff dimension. Then the condition of existence of a unique invariant set and the relationship between the invariant set and the repellers are obtained. Finally, for a larger coefficient λ, the Hausdorff dimension of fλ(x) repellers is estimated. For the coefficientλon interval(0,1］, the dynamical properties of fλ(x)iteration are studied respectively. The conclusion of the study is more likely to be applied to the corresponding biological population model than the traditional method.