The Neomicrocalamus prainii is a kind of small climbing bamboo，which could be used for both shootand timberusing purpose. The morphological and anatomical characteristics of the floral organs were described using anatomical observation and paraffin sections, so as to provide new theoretical information for the reproductive biology of bamboo plants. The results were showed as follows: (1) the inflorescence belonged to the indefinite inflorescence, and there was no pedicel. The mean length of the spikelets was 2.98 cm, and each spikelet contained 3-5 florets with a sterile flower at the top. There were 2-4 bracts at the base of the spikelets, and the mean length of the rachilla internode was 0.52 cm. (2) The florets contained 1 lemma, 1 palea, 3 lodicules (among which the two ones were bigger than the third one, and the edges were glabrous), 6 stamens and 1 pistil. The stamens were shuttleshaped and the stigma was threelobed and feathery. (3) The mature pollen grains had twonucleus and one germinal aperture. The anther was four sporangiat, and the anther wall was composed of four layers: epidermis, endothecium, middle layer and tapetum. The tapetum was glandular. There were many abnormal phenomena that could be observed in developing anthers. (4) The ovary was unilocular, parietal placentation, with dualintegument enclosing the anatropous ovule. Megaspore mother cell developed directly from a sporogenous cell, and a megaspore at the chalazal end differentiated into a functional megaspore, which formed a multicore embryo sac after mitosis until maturation. The study indicated that apparently abortive phenomenon occurred in the gametophytes of N. prainii, but most of the gametophytes were normal, and the low seed setting rate is correlated with internal factors, and the external environment is also an important factor.