水芹（学名：Lepidium sativum）是十字花科独行菜属的多年生植物，是人类一种重要的可食用绿色蔬菜，最典型作为配菜或作为叶菜类蔬菜。水芹被发现含有大量的铁、钙和叶酸、维他命A和C。

Cress (Lepidium sativum), sometimes referred to as garden cress to distinguish it from similar plants also referred to as cress (from old Germanic cresso which means sharp, spicy), is a rather fast-growing, edible herb.

Garden cress is genetically related to watercress and mustard, sharing their peppery, tangy flavor and aroma. In some regions, garden cress is known as mustard and cress, garden pepper cress, pepperwort pepper grass, or poor man's pepper.