Abstract: Tugarineuia mongolica has a tubular stylaar nectary located at the base of the style.The necta-ry, which lacks special vascular bundleis , is composed of secretory epidermis and nectariferous rissue.Stomata are present in the epidermis and there are well-developed space under them. The basal cells of the nectary are adjacent to the vacular bundle of the style During the development of nectary, both the struc-ture and content of cell change regularly. The pre-nectar is provided by the vascular bundle at the base of the style . Nectat is formed in nectariferoud tissue, and it is exareted from the stoma. The relationship be-tween the structure of the nectary and evolution is discussed.

Key words: Tugarinouia mongolica