Abstract: Based on the one-dimensional nonlinear mass-spring model, the dynamic responses of foam beam under different impact loadings were analyzed. Under the condition that the initial loading impulses are the same, the elastic-plastic stress wave propagation in the foam beam, as well as its dynamic performance, was investigated for rectangle, sine, triangular or anti-triangular loading. Based on these results, the critical loading/loading impulse was proposed for different loading shapes. The results presented in this paper are helpful in clarifying the dynamic responses of cellular materials under different loadings, and provide theoretical guidance for the dynamic design of foam structures under different working conditions.