Abstract Napier grass, also known as Pennisetum purpureum, is widely planted throughout Malaysia. It is commonly used as forage to feed cattle, and has high productivity of up to 150 tonnes per hectare per year. High yields give it the potential to contribute alternative natural fibers for use in composite materials in the automotive, construction, and aerospace industries. There have been many studies on natural fibers such as kenaf, hemp, jute, and sisal. These are garnering the attention of researchers and industries for use in different polymer composite-based products, thanks to the increased environmental awareness of consumers. Relatively few studies have been performed on Napier grass fiber-reinforced polymer matrices, or on polymeric composites/hybrid composites, to investigate their mechanical properties. Napier grass fiber was extracted as single fibers using a water retting process. This chapter reviews and summarizes several previous studies on the subject to outline the mechanical properties of the single-fiber and reinforced-composite structures. Other issues are reported that might be valuable to further research in this field, including chemical composition, physical properties, scanning electron microscopy, mechanical investigations such as tensile and flexural tests, and surface characterization. The collated information provided in this review will benefit researchers attempting to produce compatible polymer composites for industry. There are potential applications of these material polymer composites in several industries, including aerospace, automotive, and construction.