Abstract: This paper deals with the pollen grains of 11 genera, 22 species in Chinese Oleaceae. A comparative study on the pollen grains was carried out by means of scanning electron microscope and light microscope. The pollen grains of the family Oleaceae are almost spheroidal, oblate and prolate, in polar view tlie majority of the pollen grains are tri-lobulate-circular, the minority are tetra-lobulate-circular and dilobulate-circular. Pollen size: (15-65) × (12- 60)μ, 3-colporate and 3-colpate the minority of the pollen grains 4-colpate and 2- colpate colpus usually distinct and the en doaperature vague. The exine oonsists of two layers, the sexine thicker than the nexine, with big reticulum or fine reticulum, the majority of the reticulum are very distinct. On the basis of the pollen size and exine ornamentation, the pollen grains are divided into following two main types: (1) The larger pellen grains and the exine with big reticulum are found in the genera: Jasminum, Nyctanthes, Ligustrum, and Syringa. (2) The smaller pollen grains and the exine with finer reticulum are found in the genera: Osmanthus, Olea, Chionanthus, Fraxinus, Forsythia, Fontanesia and Linociera. In view of the features of pollen morphology, this family is much similar to the family Itamamelidaeeae. For example, the first pollen type resembles the genus Coryiopsis of the family Hamamelidaceae, but there are some differences between them, the former with a bigger reticulate exine and without any colpal membrane, the latter with a finer reticulate apocolpium and eolpate membrane. The second pollen type is much similar to that of the genera Hamamelis and Loropetalum of family Hamamelidaceae.