Abstract:The waterlogging tolerance of self-rooted cucumber （Cucumis sativus L.） seedlings and grafted seedlings with pumpkin (Cucurbita ficifolia Bouchc ) and loofah Luffa cylindrica（L.）Roemas stocks was studied. The results showed that grafted seedlings with loofah as stock had high root activity and high chlorophyll content during waterlogging stress; the electrolytic leakage rate, content of malondialdehyde(MDA) and superoxide free radical in roots were evidently lower than that of self-rooted cucumber seedlings and grafted seedlings with pumpkin as stock; the activities of cell protective enzymes such as superoxide dismutase (SOD),peroxidase (POD) and catalase (CAT) were higher than that of self-rooted cucumber seedlings and grafted seedlings with pumpkin as stock. The results indicated that the waterlogging tolerance of cucumber seedlings was increased b y grafting with loofah as stock.