Abstract: Polylactide (PLA) cross-shaped ribbed plates and Voronoi-based closed-cell foam structures were prepared using 3D printing technology. A rib-reinforced foam partition-filled thin-walled tube structure (RFFT) was proposed and the crushing performance of RFFT under quasi-static lateral compression was investigated. The results show that the failure sequence of the constituent elements within RFFT structure as well as the interaction between the elements changes with the location of the lateral load. Typically, for RFFT structures, the force-displacement responses and the crushing performance (i.e., the peak force, the mean crush force, the specific energy absorption, and the crush force efficiency) exhibit anisotropic characteristics. For two typical loading scenarios (i.e., lateral loads acting on the foam-filled and -unfilled zones of RFFT structure), the specific energy absorption of RFFT structure is increased by 125.16% and 129.22%, respectively, compared to the empty tube structure, whereas the peak force is found to be reduced by 5.54% and 31.28% compared to the fully foam-filled structure. Moreover, the finite element model was adopted to analyze the influence of design parameters and reveal the energy absorption mechanism of the partition foam-filled structure. Finally, the complex proportional assessment method was introduced to comprehensively evaluate the crashworthiness of RFFT structure with multiple indicators.