Triangle pearl mussel (Hyriopsis cumingii) is a superior Chinese freshwater pearl mussel species. After harvesting the pearl from the mussel large quantities of by-products are generated as waste, which includes meat, mantle and mussel tears. However, it is known that processing by-products are rich sources of nutritional substances. The present study briefly analyzed the chemical composition and characterization of mussel by-products. Especially, this paper summarized the research progress of bioactive compounds from mussel by-products such as polysaccharide, protein and peptide. Future research prospects of bioactive compounds from mussel by-products are also outlined.