Chitosan-based nanofillers are emerging as sustainable alternatives to synthetic coatings and packaging materials in agriculture. The unique properties of chitosan, including biodegradability, antimicrobial activity, and film-forming ability, make it a promising material. This chapter explores the synthesis of chitosan-based nanocomposites, their physicochemical properties, and their role in enhancing food preservation. Comparative analysis of mechanical strength, barrier properties, and active functionalities through nanotechnology is presented. The findings suggest that nanofiller reinforcement significantly improves packaging performance, reducing postharvest losses, and addressing environmental concerns related to plastic waste.