This research investigates the crashworthiness characteristics of 3D-printed Thin-Walled Multi-Cell Structures (TWMCS) through experimental testing and numerical modeling. Numerical modeling was developed based on quasi-static experimental testing of TWMCS fabricated from 3D-printed PLA material. The comparative analysis reveals differences in Crushing Force Efficiency (CFE) and Specific Energy Absorption (SEA) values of 6.89% and 7.82%, respectively, between experimental and numerical results. The TWMCS, optimized through numerical simulations, exhibited an increase in energy absorption capacity per unit mass from 6.94 J/g to 10.22 J/g. Additionally, the CFE value improved by 47.32% compared to the initial design. The findings provide valuable insights into the optimization of crashworthiness in 3D-printed TWMCS, contributing to advancements in the design of aeronautics technology. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2025.