Abstract: Abstract The genus Heracleum (Umbelliferae) consists of over 70 species. So far, 26 species and 3 varieties of them are found in China; about 25 species and 1 variety distributed in Sorth -westen China. Hengduan Mountains is one of the another centers of distribution in the world. In the present paper, pollen morphology of 16 species of the genus Heracleum from this area was investigated. Pollen grains of all the species were examined by LM, SEM. Among them 14 species were palynologically reported here for the first time. The study showed that pollen grains of Heracleum in vary shape. Their framework was trigonal in solid form, tricolporate, pleurotreme and exine 2-lauered. The stratification of exine was clear and columellae usually were distinct.

Key words: Heracelum