Abstract: The floral vascular anatomy of Myosoton aquaticum and Stellaria media were compared by paraffin section,which supplied scientific data for systematy.Results on the floral vascular anatomy showed that:(1)Vascular of pedicel had three bundles that an unclosing ring,which scattered within the central region.(2)At the top-pedicel,bundles formed a closing meristem ring.(3)The meristem ring was radially divided into ten parietal bundles.Each bundle was divides into two,with 15 bundles linked to the sepals and five linked to the petals.These five bundles divided again to from 10 petal vasculars.(4)The meristem ring was radially divided into 10 bundles from stamen vascular.(5)In the locular region,the meristem ring was radially divided into four locular parictal bundles.Each locular parictal bundle divided into three to from 12 placental bundles,which were linked to the ovule everyone.The ovary wall had 16 bundles.It is appropriate that M.aquaticum belongs to Stellaria,based on the high similarity in vascular anatomy of M.aquaticum and S.media.