Additive manufacturing technology offers huge potential for practicing the circular economy, automation in construction, and mass customization in production. It offers freedom in the design, fabrication, and development of novel structures in construction. Environmentally sustainable construction can be promoted by utilizing forest-based products and earthen materials using this technique. There are several studies on the 3D printing of earthen-based material, such as clay, using natural fibers. However, the study on clay 3D printing using forest-based materials is limited. This study proposes optimizing formulations for 3D printing based on clay, wood particles, and water content. Furthermore, this research delves into the impact of printing parameters and materials (wood particles, water content) on the buildability of 3D-printed structures. The result shows that an increase in nozzle size, i.e., extrusion rate, shows a positive impact on buildability, while higher printing speed has a negative impact on buildability. Similarly, wood particles have shown a reinforcing effect, whereas higher water content has reduced the buildability height. The result shows that the average buildability of the mixture ranges from a minimum of 17 mm (mix design: clay, 5 wt.% wood particle, 0.5 wt. % xanthan gum, 70 wt.% water content printed at 90 mm/s using 3 mm nozzle diameter) to a maximum of 236 mm (mix design: clay, 10 wt.% wood particle, 0.5 wt.% xanthan gum, 50 wt.% water content printed at 30 mm/s using 6 mm nozzle diameter). Furthermore, this study briefly discusses the opportunities for future research in this field.