Submerged cultivation techniques in mushroom biotechnology have advanced significantly, yielding diverse bioactive compounds. Managed by specialized bioreactors, this method optimizes fungal growth, producing valuable molecules like proteins, enzymes, and polysaccharides. Temperature, agitation, pH, dissolved oxygen, and inoculum quality must be precisely controlled to maximize biomass and bioactive compound yields. Stirred-tank and airlift bioreactors are commonly used across different scales for mushroom cultivation. Research aims to enhance yields and streamline production processes, offering promising avenues for nutrition, pharmaceuticals, and industry. Optimizing cultivation conditions significantly impacts fungal growth and bioactive compound synthesis. Various carbon sources like glucose and xylose affect cellulase production differently in Pleurotus ostreatus strains. Nitrogen sources, organic and inorganic, play pivotal roles in cellulolytic enzyme biosynthesis. Temperature regulation is crucial due to species-specific growth optima. Dissolved oxygen levels profoundly influence aerobic cell growth, requiring adequate oxygen transfer. pH adjustments maintain favorable growth conditions, impacting mycelial growth and metabolite synthesis. Proper agitation balances oxygen transfers while minimizing shear stress, optimizing biomass production. Inoculum size and age significantly influence mycelial yield and bioactive compound production. Mushroom mycelia show potential in various industrial sectors due to their bioactive compounds, despite regulatory challenges.