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Continuous fiber reinforced composites are widely used in thin‐walled structures due to their high specific strength and stiffness. In this work, continuous natural fiber was introduced into thin‐walled biocomposite structures via 3D printing technique to enhance energy absorbing properties and promote ecological compatibility. The effects of varying configurations of printing speed, layer thickness, and path optimization on the deposition quality of continuous ramie fiber and polylactic acid matrix were explored. The results showed that reduced printing speed (100 mm/min) and optimal layer thickness (0.25 mm) effectively minimized structural forming defects. In addition, further enhancements in the printing quality could be achieved by smoothing the path with rounded corners. Based on optimal printing strategies, different configurations of thin‐walled biocomposite structures were fabricated. Lateral monotonic and cyclic load tests were performed to investigate their energy absorption and shape recovery capacities. When the loading displacement was 10 mm (strain was 20%), the circular structure presented good shape recovery capability, with measured recovery ratio remaining above 89%. The hexagonal structure showed a similar variation in shape recovery ratio as the quadrangular structure, both remaining above 75%. Moreover, the specific energy absorption of all the structures converged after two cycles, indicating their remarkable and stable repeatable load‐bearing capacity. Highlights: Continuous ramie fiber reinforced thin‐walled structures were prepared.The deformation patterns of structures under lateral compression were analyzed.Energy absorption and shape recovery radio were studied under cycle loading.Printed structures exhibited great and stable repeatable load‐bearing capacity. [ABSTRACT FROM AUTHOR]

3D‐printed continuous natural fiber reinforced biocomposites have promising prospects due to their environmental friendliness and suitable mechanical properties. Understanding the dynamic mechanical properties of 3D‐printed biocomposites is essential to expand their application. In this study, the continuous ramie fiber reinforced biocomposites (CRFRC) with different layer thicknesses and hatch spacings were fabricated via 3D printing technique with microstructure characterized. In addition, the dynamic strengths of 3D‐printed CRFRC at four strain rates were investigated. The experimental results exhibited that the printing parameters presented nonlinear and interactive influences on the dynamic strength of CRFRC. Given this circumstance, machine learning methods were employed to link the dynamic strength of 3D‐printed CRFRC with different printing parameters. The experimental data were used to train, calibrate, and validate the machine learning models. The trained models were then utilized to predict the dynamic strength of CRFRC printed using different conditions. Behaviors under multiple strain rates were investigated over the whole parameter space. A good agreement was found between experimental results and predictions. Based on the prediction results, the relationships between parameters, microstructural characteristics and dynamic strength of printed CRFRC were quantitatively analyzed. [ABSTRACT FROM AUTHOR]