Abstract: canning electron microscopy（SEM）had been widely used in the study of palynomorphology.However,it was difficult to directly observe the morphology of pollen grains in Pollinium. In this paper,westudied the sample preparation method for obvervation pollen grains in pollinium. The pollinium of Dendrobium cariniferum Rchb. f. was used as the material,based the conventional SEM sample preparation,the pollengrains inside the pollinium were exposed by the conductive double-sided tape breaking method and thenobserved by SEM. The stereoscopic shape,size and surface texture of pollen grains were observed clearly underthe SEM. This method was simple,easy to operate and can be used as a general method to observe themorphology of pollen grains in pollinia by SEM after further optimization.