Abstract: Based on the equivalent elastic foundation beam model describing the single fiber pullout behavior in engineered cementitious composites (ECC), an improved model was established by plane strain finite element analysis of the fiber-matrix system section, proposing an explicit calculation method for the spring restrained stiffness of the equivalent continuous beams. The model was applied to the numerical simulation analysis of uniaxial tensile strain hardening and multi-joint cracking behavior of ECC. The stress-strain relationship curves of ECC were calculated based on the frictional pulley model and the equivalent elastic foundation beam model, respectively, and compared with the experimental results. The results show that for polyethylene fiber (PE)-ECC, the calculation results based on the equivalent foundation beam model are in better agreement with the experimental results. It indicates that the improved equivalent foundation beam model proposed in this paper can well describe the pull-out behavior of fibers whose flexural stiffness cannot be neglected, and is of reference value for the force mechanism and design theory of such ECC materials and structures.