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The pollen morphology of 20 species from <i>Blumea</i> and <i>Cyathocline</i> Cass. was investigated using a light microscope (LM) and scanning electron microscopy (SEM) to explore their taxonomic significance. This study showed that pollen grains of these species were usually tricolporate, rarely tetracolporate (<i>B. sinuata</i>). Nine pollen types were distinguishable through the exine sculpture characters and the number of apertures. It was easily distinguished <i>Cyathocline</i> from species of <i>Blumea</i> s. str. by its much smaller size (15.04 μm × 15.07 μm) and sparse and longer spines (24 spines, spine length 4.23 μm) with acute apex, which suggest that <i>C. purpurea</i> might not belong to the genus <i>Blumea</i> s. str. The palynological characteristics indicated that Section <i>Macrophllae</i> and Section <i>Paniculatae</i> of <i>Blumea</i> were not monophyletic groups. The pollen morphology differentiation of <i>B. lacera</i> clade is consistent with the interspecific relationship revealed by the molecular phylogenetic tree. However, the pollen morphology of the <i>Blumea densiflora</i> clade is inconsistent with the interspecific relationship based on molecular phylogenetic analysis. This palynology research can only partly support the previously published molecular phylogeny of <i>Blumea</i> s. str.