Abstract: Carbon fiber reinforced plastics (CFRP) are of high specific strength, specific stiffness and significant lightweight effect. Therefore, CFRP thin-walled structures are widely used as energy-absorbing devices in engineering fields. This paper took unidirectional CFRP as research object. The micro-scale structural parameters and fiber volume fraction were obtained by using scanning electron microscope. Then, a representative volume element (RVE) was established, which was capable to accurately reflect its micro morphology. By applying periodic boundary conditions and unit load, the macro equivalent elastic parameters were acquired and then verified by experimental tests. Subsequently, the failure criterion and damage evolution equation based on micromechanics were developed. Combined with the mechanical characteristics of unidirectional CFRP, the macro damage model was developed, and finally forming a set of multi-scale damage model based on micro failure. On this basis, the crashworthiness performance of CFRP thin-walled circular tube under axial quasi-static load was numerically explored, and the numerical results were verified through the crushing test. Based on the verified multi-scale finite element model, the effects of carbon fiber ply angle and carbon fiber volume fraction on the crashworthiness were investi-gated. The results show that the ply angle and carbon fiber volume fraction have great impact on the crashworthiness characteristics of CFRP thin-walled structures.