SummaryFlammulina velutipes (F. velutipes) is one of the most widely consumed edible mushrooms worldwide. The growth of F. velutipes involves two primary stages: the mycelium and fruiting body. Unique polysaccharides are produced in each stage; mycelial polysaccharides (FVMPs) are produced during the mycelial fermentation stage, while fruiting body polysaccharides (FVFBPs) are produced during the fruiting stage. These polysaccharides, the major bioactive components of F. velutipes, have garnered significant attention due to their various functions and activities. Notably, they exert functional activities by mediating gut flora, including antioxidant, anti‐inflammatory, and immunomodulatory properties, reduce blood sugar and lipid levels, and enhance cognitive performance. This study examined the variations in FVMPs and FVFBPs resulting from different extraction and purification methods, with a specific focus on delineating their distinct structural characteristics. This study further explored the impact of the structural composition of FVMPs and FVFBPs on their health‐promoting properties, focusing on the relationship between their structures and their functional and biological effects. Finally, this study outlines future research avenues designed to contribute to the ongoing research in the field of bioactive FVMPs and FVFBPs.