Based on the fact that existing bend component is tend to produce inflection point on the steel strand by its small radius, the experiment is designed to study the influence of steel strand mechanical properties by bend component with specific radius R and bending angle θ. The law and mechanism of ultimate strength, ductility of steel strand and prestressing loss due to friction affected by R and θ is analyzed detailly. The results show that the radius of bend component should be as large as possible to improve the mechanical property of steel strand, and it shouldn't less than 100mm when the size is limited. In addition, the uniform calculating formulas of prestressing loss due to friction is presented based on experiment data, which take the affection factor of R into account.