荆芥内酯（英语：Nepetalactone）是一种内酯化合物，最早是于1941年从一种猫薄荷植物Nepeta cataria中通过水蒸汽蒸馏的方法分离出来。

荆芥内酯是一个有双环的类单萜，其分子含有两个稠合的环，分别是环戊烷和一个六元的内酯。结构和效用都与缬草素（valepotriate）相似。另外拥有多种同分异构物。

4aα,7α,7aα-荆芥内酯为Nepeta cataria所含有的活性化学物质，可对大约75%的猫产生特殊作用。猫对此物质的反应与基因有关，感知的位置为嗅上皮（olfactory epithelium）。

Nepetalactone is an organic compound, first isolated from the plant catnip (Nepeta cataria), which acts as a cat attractant. Nepetalactone is bicyclic monoterpenoid, i.e., it is a ten-carbon compound derived from isoprene with two fused rings: a cyclopentane and a lactone. It belongs to the class of iridoids. The structure and the effects of the compound are similar to those of valepotriates. A number of isomers of nepetalactone are known.