Abstract:In this paper, we made a comparison between the differences and similarities in the constitutions and structures of 16 species of vines and trees in Celastraceae inhabiting various growth environments and a preliminary study on the relations among the structures, living habits and growth environments of vines and trees. Our purpose is to provide some reference material for the study of the evolution trend of secondary xylem and the evolutional position of vines in taxonomy. Celastrus, Tripterygium and Monocelastrus of this family are typical in vine structure; their secondary xylem posses a higher level in specialization; members in Euonymus are vines or trees, but the vines are similar to the trees in structures, displaying a series of primitive and conservative characters. Therefore, the evolution of growth habit and that of secondary xylem of Celastraceae are non-synchronous. In addition, the constitution of elements of secondary xylem between genera are non-synchronous as well. This will provide some anatomical evidences for continuative studing on evolution of Celastraceae.