High-quality RNA isolation from recalcitrant adipose tissue with high lipid content and low cell numbers is difficult. Many studies have made efforts to optimize methods for isolating RNA from adipose tissue through combinations of column-based kits and phenol-chloroform methods, or through in-house protocols. However, the considerable complexity of these protocols and the various kits/materials required hamper their wide use. Herein, we describe an optimized protocol based on TRIzol reagent, which is the most accessible ready-to-use reagent for nucleic acid and/or protein isolation in laboratories. This article provides a step-by-step protocol yielding sufficient and qualified RNA from lipid-rich specimens for downstream applications.