In this paper a dual-stage bistable structure with elastic collision（DSBSEC）is proposed，which is a two-degree-of-freedom（DOF）structure consisting of a bistable nonlinear stage and linear stage. The bistable nonlinear restoring force is introduced into the bistable stage by the oblique spring. The elastic collision is introduced by the springs installed on vibrator motion track on the either side of the centerline. Owing to the collision，the large-amplitude inter-well oscillation of the bistable stage is significantly enhanced，leading to a better vibration energy harvesting performance. A dynamic model of the dual-stage bistable structure（DSBS）without the elastic collision is presented，which is experimentally validated. Based on the dynamic model，the governing equations of the DSBSEC are deduced. Using the parameters of the experiment，the numerical simulations of the DSBSEC are performed. The results show that，compared to the DSBS，the DSBSEC can significantly improve the vibration energy harvesting performance，e. g.，the bandwidth is broadened by over ten times（1150.0%）and the maximum generated power is improved by 168.2% when the excitation amplitude is 3.3 m/s2. Through the numerical simulations，the nonlinear dynamic features of the proposed structure are thoroughly discussed，where the structural phase portraits with respect to some excitation frequencies are given.The parametric study reveals how the system performance is influenced by the collision distance and symmetry.