马尾树（Rhoiptelea chiliantha ），是马尾树属唯一物种，生长在中国云南、贵州、广西一带和越南北部山区，是中国的特有种，和胡桃科各属亲缘较近，是第三纪孑遗植物。

落叶乔木，树高约17米，奇数羽状复叶，互生，圆锥花序，花序下垂，长达32厘米，外形类似马尾，因此得名。花两性同株。小坚果卵圆形，有翅。是中国国家二级保护植物品种。

Rhoiptelea is a monotypic genus of flowering plants in the Juglandaceae family. It contains a single species, Rhoiptelea chiliantha, commonly known as the horsetail tree. This genus was previously recognized in its own family, Rhoipteleaceae, but the APG III system of 2009 placed it in the Juglandaceae family. Rhoiptelea chiliantha is native to southwest China and north Vietnam and lives at the elevation of 700-1600m in mountainous areas. The trees are wind-pollinated, the flowers arranged in large sagged panicles usually 32 cm long like horse tails, and the fruit is a small botanical nut with rounded wings. The leaves are pinnately compound and papery. The trees are usually 17 m high and with 40 cm diameter. It is a protected species of China.