Abstract: Fresh Lotus seeds were used as raw materials to prepare and characterize crude polyphnol oxidase (PPO) extract. The results showed that PPO enzymes from Lotus seeds had the highest activity at 45⁵0℃ and pH 6.5⁷.0, the enzyme had the highest stability when pH was neutral. Ca2 +、Mn2 +、Fe3were effective in promoting PPO activity. Copper ion was highly effective in inhibiting PPO activity. PPOs were inhibited by reductants, such as sodium bisulfite and sodium sulfite. The purpose of this study was to provide a theoretical basis for inhibiting lotus seeds from browning effectively.