ABSTRACT This study investigated the comparative influence of different compositions (3 wt. %, 6 wt. %, 9 wt. %, 12 wt.%, and 15 wt. %) of treated plantain stem fiber (PSF) and plantain leaf fiber (PLF) on selected properties of the epoxy-based composite. These plantain fibers and epoxy resin were mixed based on predetermined compositions and stirred using a stirrer at an ambient temperature for 3 minutes before pouring into a mold using a hand layup process. The composites were allowed to cure within 2–3 hours. Mechanical (tensile, flexural, impact, and hardness), wear, thermal conductivity and water absorption properties, and surface morphologies of the developed composites were investigated. The study revealed that the optimum properties were attained at 9 wt.% and 12 wt.% PSF and PLF except for wear and water absorption that occurred at 15 wt.%. The PSF gave more enhancement in all the properties except for impact strength. Hence, from the combination of properties obtained, these bio-based fibers can be used to improve the conductivity of eco-friendly and biodegradable polymer-based composites for electrical/electronics, biomedical, automobile, and building applications.