<p>Black Soldier Fly <i>(Hermetia illucens L.)</i> larvae have emerged as a promising biological agent for sustainable waste management and high-value biomass production. Owing to their rapid growth rate and exceptional capacity to convert heterogeneous organic residues, including lignocellulosic substrates such as rice straw and bagasse, BSF larvae facilitate efficient bioconversion of low-value wastes into nutrient-rich biomass and frass. The larval biomass is characterized by elevated concentrations of proteins, lipids, and essential minerals, rendering it a viable alternative ingredient in poultry, aquaculture, and livestock feed formulations. Recent investigations extend the relevance of BSF beyond feed applications. The synergistic activity of larval gut microbiota facilitates the degradation of complex organic matter and the generation of biofuels. Additionally, larval extracts exhibit bioactive, immunomodulatory, and chitin-rich properties, offering potential applications in pharmaceuticals, cosmetics, and biodegradable materials. Moreover, BSF systems have demonstrated efficacy in heavy-metal remediation, faecal sludge stabilization, and the synthesis of bioactive polysaccharides and other industrially valuable biomolecules.</p><p>This review highlights the potential of BSF larvae as a cost-effective and ecologically sustainable bioconversion platform, integrating organic waste valorization with the production of renewable animal feed, bioenergy, and value-added bioproducts. Nevertheless, large-scale commercialization requires further research to optimize rearing parameters, refine extraction methodologies, and establish regulatory standards to ensure product safety and economic viability.</p>