Abstract: The morphological characteristics of the microspores of 28 species and the megaspores of 26 species in the family Selaginellaceae from China were observed in detail by using scanning electron microscope. The ornamenta-tions cf both spores of different species in the Selaginellaceae are diver-sified and stable. The larger ornamentations are always composed of the regular smaller ones. The ornamentations of both spores in the same spe-cies are not similar. Acconding to the morphological characteristics of the spores the authors support the view that the Selaginellaceae divide into 2 groups (2 genera or one genus divide into 2 sub genera) i. e. Homeophyllum and Heterophyllum, and suggest that Heterophyllum may be subdivided into 5 group. On the basis of the ornamentations of spores the relationship in the family are discuused.