The morphology of spores of 25 species of Selaginellaceae from China was examined using scanning electron microscope (SEM).The results show that:(1)The megaspores are tetrahedral-globose,with a trilete,each of which has a length of about 1/2~3/4 of the spore radius.The megaspores are often rounded triangular or suborbicular in polar view,and suborbicular,fan-shaped or nearly elliptic in equatorial view.The length of polar axis is about 158~548 μm.The length of equatorial axis is about 196~675 μm.(2)The microspores are also tetrahedral-globose,with a trilete,each of which has a length of about 1/2~3/4 of the spore radius or almost equal to radius of the spores.The microspores are always suborbicular or rounded triangular in polar view,and suborbicular,nearly fan-shaped in equatorial view.The length of polar axis is about 10~40 μm.The length of equatorial axis is about 17~63 μm.(3)The ornamentation of the spores includes granulate,tuberculate,verrucate,spinate,baculate,reticulate,lamellate,verrucate-rugulate,and cerebriod.The spore morphology characteristics can be used as the criterions for the classification of subgenus and species of Selaginellaceae.