泽泻属（学名：Alisma）是泽泻科下的一个属，为水生草本植物。该属共有10种，分布于北温带和大洋洲。

Alisma is a genus of flowering plants in the family Alismataceae, members of which are commonly known as water-plantains. The genus consists of aquatic plants with leaves either floating or submerged, found in a variety of still water habitats around the world (nearly worldwide). The flowers are hermaphrodite, and are arranged in panicles, racemes, or umbels. Alisma flowers have six stamens, numerous free carpels in a single whorl, each with 1 ovule, and subventral styles. The fruit is an achene with a short beak.