Abstract: Taking Taraxacum ohwianum kitam as test materials, the effects of lead（Pb） stress on biomass, cell morphology and physiological indexes of dandelion（Taraxacum ohwianum Kitam） were studied by adding exogenous heavy metals and pot experiments, in order to provide reference for the remediation of Pb pollution in dandelion.The results showed that with the increase of Pb concentration, the increment of fresh weight of overground part and underground part of the treated group decreased significantly compared with the control group.The plant height decreased with the increase of Pb stress concentration, and the epidermal cell volume increased significantly, the number of cortical cells increased, the number of parenchyma cells decreased, and even the number of intercellular spaces, endodermis cells and stellars decreased.The upper and lower epidermal cells of the leaves were irregular in shape, and the number of epidermal cells also increased.Under Pb stress, SOD and POD activities in roots and leaves increased first and then decreased, while CAT activity in leaves increased.The activity of CAT in the root decreased.Under Pb stress, MDA content in leaves showed an increasing trend.The MDA content in root showed an increasing trend and decreased at the later stage of stress, and the MDA content in root was higher than that in leaf under the same stress concentration.Chlorophyll content under Pb stress decreased with the extension of stress time.The morphological structure and physiological characteristics of dandelion showed good tolerance to Pb stress, which provided a theoretical basis for the application of Pb pollution remediation of dandelion in Northeast China.