This review explores the development of chitosan-based nanofilms reinforced with agricultural waste fillers, offering a promising approach to sustainable food packaging. By integrating chitosan's natural properties�biocompatibility, biodegradability, and antimicrobial activity�with mechanical improvements gained from agricultural waste fillers, these nanofilms provide a substantial enhancement over conventional plastic packaging. The incorporation of natural fillers (e.g., cellulose, starch, and lignin) derived from agricultural byproducts not only strengthens the films but also promotes waste valorization, contributing to a circular economy. These nanofilms effectively address key challenges in the packaging industry by improving moisture and oxygen barriers, enhancing durability, and offering antimicrobial protection, all of which are essential for extending shelf life and preserving the freshness of perishable goods. Unlike traditional plastics, which pose significant environmental risks due to their long-term persistence, chitosan-based films naturally biodegrade, reducing their ecological footprint. The review highlights advancements in the synthesis and functional optimization of these nanofilms, showing their capability to meet the stringent requirements of food packaging. Moreover, the use of agricultural waste in production aligns with global sustainability efforts, offering the dual benefit of enhancing packaging properties while reducing agricultural waste. Nevertheless, the review acknowledges several challenges to commercialization, such as the need for cost-effective large-scale production methods and ensuring regulatory compliance with food safety standards. Overall, the potential of chitosan-based nanofilms to replace conventional plastics in packaging is clear, as they offer a sustainable, high-performance alternative with both environmental and practical advantages.