Presently, novel materials based on natural fibers are emerging daily to replace synthetic fibers in various engineering disciplines, as they minimize environmental pollution, allow for easy processing, provide superior strength, and promote industrial sustainability. The global demand for novel eco-friendly fibers for composites has paved the way for this work. This work uses epoxy as a matrix material, and polymer composites with reinforcement from untreated and alkali-treated Zanthoxylum acanthopodium bark fibers (5–25 wt.%). Hand lay-up was used in the development of the epoxy composites. The mechanical characteristics and water absorption rates of the produced epoxy composites were evaluated following ASTM standards. Epoxy composites containing 20 wt.% of alkali-treated Zanthoxylum acanthopodium bark fibers had excellent mechanical qualities, including an ultimate tensile strength of 47.3 MPa, according to the test findings. However, there was a positive correlation between fiber loading and water absorption. The fiber bonding and void properties of the investigated composites were viewed with a scanning electron microscope.