Aims The study of embolism vulnerability to drought has become a hot and key topic under global climate change. The objective of the study was: 1) to identify the relationship between xylem structure and embolism vulnerability; 2) to define the differences in resistance of embolism in xylem structure of each species; and 3) to establish drought tolerance indexes in xylem structure of six species. Methods Drought tolerance trees of Robinia pseudoacacia, Hippophae rhamnoides, Ulmus pumila, Corylus heterophylla, Salix matsudana, Acer truncatum were studied. Cochard Cavitron centrifuge was used to establish embolism vulnerability curves and to calculate xylem vulnerability value. Staining and silicone injection techniques were used to to measure xylem structure of drought tolerance trees including vessel diameter, conduit wall span, number of vessels per unit area, contact faction, vessel length and wood density. Important findings The results showed: 1) xylem embolism vulnerability of the six species ranked as Robinia pseudoacacia > Ulmus pumila > Hippophae rhamnoides > Salix matsudana > Acer truncatum > Corylus heterophylla;2) the vulnerability curves is r shape for Robinia pseudoacacia, Hippophae rhamnoides, Ulmus pumila and is s shape for Corylus heterophylla, Salix matsudana, Acer truncatum, respectively; 3) the xylem vulnerability values is significantly different in trees of r shape and s shape (p < 0.01). Furthermore, linear analysis showed that the different effects between the xylem structure of the species was closely related to the vulnerability in the following order: the maximum effect was from wood density (t = 0.702), the medium effect was from vessel diameter (t = 0.532), and the minimum effect was from vessel length (t = 0.01).