瓶尔小草科（学名：Ophiogiossaceae）是一种蕨类。有着由孢子囊形成的短寿型孢子，诞生于和叶片分开的叶柄上；以及肥大的根。许多物种一年只会长成一片蕨叶。而有少数的物种只有能生育的穗，而非一般所谓的叶片。瓶尔小草目的配子体是在地底下的。其孢子不会在阳光之下生长，且配子体可以在不形成孢子体的状态下存活两个世纪之久。茎短直立状、肉质；叶片通常亦为肉质状，幼叶不卷旋，孢子囊枝以一定的角度着生于营养叶上。绝大多数为地生型，少数着生于树干，或为湿地植物。分布世界各地，但不常见，全世界仅有3属80种。

Ophioglossaceae, the adder's-tongue family, is a family of ferns, currently thought to be most closely related to Psilotaceae, the two together comprising the class Psilotopsida as the sibling group to the rest of the ferns. The Ophioglossaceae is one of two groups of ferns traditionally known as eusporangiate ferns. The number of genera included in the family varies between different authors' treatments, and most conservatively the family is treated as containing four genera, Ophioglossum, Botrychium, Helminthostachys, and Mankyua (placed in two to four separate families in other treatments). A broad definition of the family and its genera have been taken in several recent treatments. A notable exception is the classification of Kato, who advocated the division of Botrychium into four genera: Botrychium s.s., Sceptridium, Japanobotrychium, and Botrypus.