This chapter explores rice husk (RH), an abundant agricultural waste product, that has gained attention as a sustainable strengthening agent in wood-plastic composites (WPCs). The increasing demand for sustainable materials has spurred interest in natural fibers like RH, which exhibit beneficial characteristics, including biodegradability, low density, and excellent availability. This chapter analyzes the integration of RH as a reinforcing filler in diverse polymer composites, such as PET, PVC, PE, PP, and PS. To strengthen the bond between reinforced RH materials and polymer matrices, researchers are investigating different surface modification methods. These techniques are focused on enhancing the bond between the two substances, which is essential for the performance and longevity of composite materials. Different methods, including injection molding, extrusion, compression molding, and pultrusion, are used to manufacture reinforced hybrid (RH) composites. The performance characteristics of RH composites are greatly affected by the manufacturing method chosen. These processes highlight how flexible and versatile RH is in producing composite materials. Also, the study investigates the mechanical characteristics and physical properties of RH composites. It also covers their heat resistance and ability to disperse in water. This chapter illustrates that RH-reinforced WPCs provide an environmentally sustainable alternative to traditional composites, applicable in diverse industrial sectors.