Abstract:Morphological studies of the pollens of 21 species in four sections of genus Osmanthus from China are reported in this paper. The pollen grains are spheroidal or subprolate in shape. The sculptures of the pollen exine are unexceptionally reticulate. Most species are 3-colporate, and few are 4-colporate or with 6 apertures. The ora are obvious or not obvious. Especially, pollens of each of the nine species are 3-colpate and 3-colporate; O.hainanensis is 3 and 4-colporoidate. Transitional types of the apertur also exist in these species．Some characters indicate that the pollen aperture of genus Osrnarahus is on the transitional stage from simple to compound apertures in Oleaceae．Two types ofpollens can be divided based on whether or not the lumen become small from the center of the mesocolpium toward the colpi．Th e sculpture characters show correspondence to the sectional division of Osmanthus，and to some extents the comprehensive characters of pollen morphology have corelation with that of the structural morphology ．In general，pollen morphology presents a systematic significance in the genus Osmanthus．
