Expanded polystyrene (EPS) foam, a widely used material for packaging and insulation, presents significant environmental challenges due to its non-biodegradable nature. This chapter explores the mechanical recycling of EPS, emphasizing its importance and benefits. It covers the entire recycling process, starting with collecting and sorting EPS waste from industrial and consumer sources. Pre-processing steps, including cleaning, contaminant removal, and size reduction, are detailed to prepare the material for recycling. The core processes of mechanical recycling densification, pelletizing, and extrusion are examined, highlighting the equipment and techniques used to transform EPS waste into reusable material. Quality control measures essential for maintaining recycled EPS’s integrity, including physical and chemical property assessments and compliance with relevant standards, are discussed. Applications of recycled EPS for traditional uses like packaging and insulation and innovative applications in construction and consumer products are presented. The chapter addresses challenges such as contamination and economic viability, exploring technological advances and emerging research to overcome these issues. Through case studies and future directions, the chapter underscores the need for continued innovation and stakeholder engagement to enhance EPS recycling and foster a circular economy.