Abstract: The depletion of natural resources and the persistent accumulation of industrial waste pose significant challenges to the global environment. Seeking environmentally sustainable solutions has become paramount. Mycelium composites, prepared using fungi and waste substrates, offer promising potential as partial replacements for conventional petroleum-based composites, exhibiting broad application prospects. This review aims to delve into the principles of mycelium composites synthesis, comprehensively analyze the key factors influencing their physical and mechanical properties and systematically summarize the current applications of mycelium composites in construction, packaging, and automotive industries. Furthermore, it identifies existing challenges and future development directions for mycelium composites, providing a comprehensive reference to facilitate further research, technological development, and practical applications, thereby promoting their advancement and wider adoption.