灯心草科共有8属约400余种，分布在世界各地的温带和寒带的湿地和贫瘠土壤地带，有些品种也曾长在热带的山区。中国只有灯心草属和地杨梅属2属共约80余种，分布在全国各地，南部较少。

其中灯心草可编席，髓心入药或为灯心。

本可植物绝大部分为草本，也有灌木（如Prionium属），大部分为多年生，少数为一年生的。有匍匐状根茎和直立的茎；叶扁平或圆柱状，常绿，有时退化为膜质的鞘，在茎上分为三排，但双排草属的叶是两排，地杨梅属的叶有白色的毛；小花两性，绿色或稍白色，花瓣6，2轮，雄蕊6，稀3枚；果实为蒴果，分裂为3果瓣。

The Juncaceae, the rush family, are a monocotyledonous family of flowering plants of eight genera and about 400 species. Members of the Juncaceae are slow-growing, rhizomatous, herbaceous plants, and they may superficially resemble grasses and sedges. They often grow on infertile soils in a wide range of moisture conditions. The most well-known and largest genus is Juncus. Most of the Juncus species grow exclusively in wetland habitats. A few rushes are annuals, but most are perennials.