This paper has studied how material properties fluctuation effects on bending spring back of the high strength steel, through uniaxial tensile tests by sampling based on the orthogonal test, and found out the material mechanical properties have great fluctuation by analyzing the uniaxial tensile test data. Then FE model is established according to working condition of the actual bending machine, and the model is proved to be accurate by comparing the simulated result with the bending experimental result. At last all the uniaxial tensile data are input into the FE model respectively and the result shows that the fluctuation of the material properties has a great influence on the bending springback of the high strength steel, among which the influence of material thickness on the bending springback has reached to 2.12° and material orientation to 0.21°.