索氏[脂肪]提取器（英语：Soxhlet extractor）是一种在1879年由Franz von Soxhlet发明的实验仪器。它最初的设计是为了从固体中提取脂类化合物，但是，索氏提取器不仅仅可以用来提取脂类。一般来讲，如果待提纯的化合物在溶剂中有有限的溶解度而杂质不溶于这种溶剂，就可以使用索氏提取器进行提取（因为如果待提纯的化合物在溶剂中溶解度很高，则通过过滤就可以与不溶的杂质分离）。

一般来讲，样品是放在用很厚的滤纸制成的筒中，然后整个筒被放在索提的套管中。索提会被放在装有萃取溶剂的烧瓶上，而索提的上方会有一支回流冷凝管。

A Soxhlet extractor is a piece of laboratory apparatus invented in 1879 by Franz von Soxhlet. It was originally designed for the extraction of a lipid from a solid material. Typically, a Soxhlet extraction is used when the desired compound has a limited solubility in a solvent, and the impurity is insoluble in that solvent. It allows for unmonitored and unmanaged operation while efficiently recycling a small amount of solvent to dissolve a larger amount of material.