The aim of this study is to analyze the mechanical and metallurgical characteristics of polylactic acid (PLA) composites with the use of natural fibers that are manufactured by fused deposition modeling (FDM), which is a type of additive manufacturing. PLA is a biodegradable polymer sourced from a renewable resource, and it is almost always reinforced with natural fibers like jute, flax, and sisal to make the composite stronger and better for the ecology. The micron-sized tensile strength, flexural modulus, and impact resistance of the composites were assessed and matched against pure PLA. Besides, metallographical evaluation was additionally performed to study the effect of natural fibers on the composite of studied materials and fracture structure. The findings indicated that the addition of natural fibers remarkably enhances the mechanical loading and durability of PLA while still being biodegradable. The most important advantage of this research is the possibility of using PLA–natural fiber composites in the manufacture of products that must be lightweight, durable, and sustainable throughout their life cycles.