<p>The performance of natural fiber-reinforced composites is often constrained by weak interfacial bonding and limited durability. This study investigates the effect of chitosan incorporation on the mechanical, tribological, thermal, and moisture absorption behavior of Hennep 16 hybrid short fiber-reinforced vinyl ester composites fabricated via hand layup. Composites were developed with varying chitosan contents (1–5 vol%). Results showed that the fiber-reinforced composite (AN) improved tensile, flexural, and impact properties by 29.6%, 30.9%, and 37.5%, respectively, compared to neat resin. The addition of chitosan significantly enhanced performance, with 3 vol% (ANC1) exhibiting maximum tensile strength (144.3&#xa0;MPa, + 100.1%), flexural strength (164&#xa0;MPa, + 95.2%), and impact resistance (4.4&#xa0;J, + 83.3%), attributed to improved interfacial adhesion and efficient stress transfer. In contrast, 5 vol% chitosan (ANC2) showed reduced mechanical strength due to particle agglomeration but delivered superior hardness (89 Shore-D, + 20.2%), lowest wear rate (0.020 mm³&#xa0;Nm⁻¹), and reduced friction (0.18) owing to the formation of a protective tribo-layer. Flammability resistance showed a gradual improvement with increasing chitosan content. However, water absorption increased from 3.2% (neat resin) to 4.8% (5 vol%) due to the hydrophilic nature of fibers and filler. Overall, 3 vol% chitosan is optimal for mechanical performance, while 5 vol% enhances surface durability and functional resistance, demonstrating the potential of these composites for structural and tribological applications.</p>