This chapter examines the transformative role of lightweight bionanocomposites in advancing sustainable transportation. Focusing on their integration in sectors like automotive, aerospace, marine, and rail, it highlights how these innovative materials, crafted from biopolymers, natural fibers, and nanoscale reinforcements, offer superior mechanical strength, durability, and weight reduction—crucial for improving fuel efficiency and reducing emissions. Within the transportation industry, bionanocomposites are increasingly applied to vehicle body panels, interiors, and battery housings, as well as aerospace fuselages and wings, where their lightweight properties help achieve significant energy savings. For marine applications, bionanocomposites provide durability and sustainability in hulls and decks, offering a competitive edge over traditional materials. The chapter also emphasizes their alignment with eco-friendly manufacturing practices and their potential for recyclability, addressing sustainability and environmental impact concerns. Moreover, it delves into challenges in scaling up production and meeting regulatory standards, alongside exploring future trends that leverage these composites for greener and more efficient transportation structures. With rising demand for sustainable materials, this chapter underscores the pivotal role of lightweight bionanocomposites in reducing transportation’s carbon footprint and advancing clean energy goals.