Contemporary industries are predominantly concentrated on the advancement of bio-inspired hybrid natural fiber composites for use in lightweight biosensor chips, automotive, and microfluidic applications. In the present chapter, an investigation was conducted on the mechanical properties and morphological characteristics of alkaline (NaOH) treated hemp, flax, noil hemp, and noil flax fiber-reinforced ecopoxy bio-composites (Atmakuri et al. in Polym Basel MDPI 14:1–21, 2022 [1]). The specimens were fabricated utilizing the hand layup technique followed by the compression molding process. Two distinct sets of composites were produced with varied weight fractions. The specimens underwent testing to assess their mechanical properties, including flexural strength, interlaminar shear strength, and contact angle measurement. The treated fibers were examined through optical microscopy and Fourier Transform Infrared spectroscopy (FTIR). Morphological analyses, such as porosity and fracture mechanisms, were conducted utilizing scanning electron microscopy and SEM–EDX spectroscopy. The findings indicated that the incorporation of ecopoxy resin augments the mechanical properties, and the NaOH treatment enhances fiber properties by removing impurities. Overall, hemp/flax fiber bio-composites exhibited superior mechanical properties compared to noil hemp/noil flax fiber bio-composites. The effects of hybridization were distinctly discernible in both instances. It was noted that hybrid composites demonstrated enhanced properties compared to single fiber (individual fiber) composites.