In this study, a novel sodium anode filament was developed for Fused Filament Fabrication (FFF). The filament formulation combined Polylactic Acid (PLA) as the polymer matrix with Hard Carbon as the active material, enhanced with Poly (ethylene glycol) dimethyl ether and Carbon Black Timcal Super-P to improve plasticity and conductivity. The initial anode slurry was prepared and optimized based on capacity and cyclic voltammetry studies. The homogeneity and elemental distribution of the slurry filaments were analyzed using scanning electron microscopy and Raman spectroscopy. Filament production was achieved using a filament-making machine, followed by 3D printing with an FFF printer. Rheological analysis showed that the developed filaments had elastic and viscous modulus values similar to conventional PLA filaments, suggesting their potential for similar applications with enhanced properties. The frequency sweep test confirmed shear-thinning behavior, advantageous for extrusion and 3D printing processes. Subsequent testing showed that the 3D printed samples exhibited a 15% reduction in capacity (230 mAh/g) compared to the slurry-coated films (273 mAh/g). The printed samples displayed a less distinct voltage plateau and a higher discharge voltage profile, suggesting increased internal resistance or less efficient sodium-ion intercalation compared to slurry-coated samples. Additionally, the cyclic voltammetry of the printed samples indicated slightly lower electrochemical activity than the slurry-coated samples.