tRhizome of lotus (Nelumbo nucifera Gaertn. ssp. nucifera) has become the most popular aquatic vegetablesin the world. An important problem for its storage and process is easily browning and discoloration, whichhas been proved to mainly result from polyphenol oxidase (PPO) activity. Harvest rhizomes collectedfrom 56 varieties including wild individuals, landraces and cultivars were investigated for their PPOactivities as well as 19 morphological characteristics. Several correlations were found to exist in PPOactivity values among different parts of all rhizome knots. Four out of 19 morphological characteristicswere associated with PPO activity in different parts or knots. It was observed that the PPO activity wasuniformly distributing neither in different parts within a knot nor in all knots. The PPO activity in heartpart was lower than that in the periphery except for a special case that the 4th knot of red flower lotusrhizome. The PPO activity in former three knots with less number of stoma on skin of rhizome (SA) waslower than it in the same ones with more SA ones. The PPO activity in red-flower-lotus rhizomes waslower than that in white-flower plants. Our results also provide some clues for lotus rhizome processing.For red flower varieties, those with a few knot number of main stem of rhizome and the former threeknots can be selected in priority, while the heart part of former four knots in white flower variety shouldbe preferred. The periphery of former four knots in white flower variety that contained higher PPO activitywould be beneficial for pest and disease resistance and for breeding medicinal and functional cultivarsrelated with different phenolic compounds.