The growing concern over the environmental impact of conventional food packaging has driven the shift towards biodegradable alternatives, with edible films and coatings emerging as a promising solution. This chapter provides a comprehensive overview of the materials and methodologies of mushroom-derived edible films and coatings, integrating advanced extraction and nanotechnology techniques. Subcritical water extraction (SWE) is employed to isolate bioactive polysaccharides from mushrooms under controlled temperature and pressure, ensuring high extraction efficiency without the use of organic solvents. The extracted compounds are then utilized to formulate biodegradable edible films and coatings, enhanced with silver nanoparticles (AgNPs) to improve mechanical strength, antimicrobial activity, and barrier properties. The incorporation of AgNPs further enhances food protection by inhibiting microbial growth and reducing oxygen permeability.