Abstract:Pollen morphology of 11 species of Calligonum L. in China was examined under LM and SEM. Based on ornamentation observed under SEM,it might be divided into 4 types, viz. reticu-late-foveolate with circular or subcircular lumina, retieulate-foveolate with polygonal lumina, reticu-late-perforate and reticulate-perforate or reticulate-fossulate in the sequence of evolutionary trend. According to the shape of os, the pollen grains of Calligonum were different from those of the other genera of Polygonaceae.