Abstract: The culm_sheath as an important vegetative organ to identify bamboos is easily involute and cracked after its drop, so that most culm_sheath specimens made by classic method are poor for the identifaction of species. A new method for making culm_sheath specimen, namely “ironing_method by electric iron", is here introd uced, and the effect on the characters of culm_sheath is discussed. As a result, it is better to keep the taxonomical characters by this method, and the quality of specimen is greatly improved.