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The mechanics model, mechanical property of crop stalks, and the influence on its mechanical property by microstructure of crop stalks were overviewed. By now, the study on mechanics property of crop stalks is still on the reference of the mechanics index of engineering material, and the mechanics model is still based on taking crop stalks as isotropic material. The complex structural, viscoelasticity and anisotropic property of biological material had not been well reflected in those studies. The viewpoint presented in the paper for studying crop stalks mechanics is that studying its features of structure and function by the view of material science, establishing mechanical model and mechanical property index system based on the material model, and building up the constitutive equation and the strength criterion of crop stalks material cab.