Abstract:Using the root back reference standards of five species in Paeonia genus, Cortex Moutan obtained from seven Chinese pharmaceutical works was identified microscopic ally. The quantitation of paeonol in Cortex Moutan and Liuwei Dihuang Wan was made by means of ethanol extraction and duat wavetength TLC scanning. This method reparated all impurities and was compared with the methods of water-distillation-UV spectrometry and ethanol extraction-UV spectrometry. The results are exact and dependabte.