We describe here an analytical method of HEK293 α1A AR cell membrane chromatography (HEK293 α1A AR/CMC) combined with reverse phase liquid chromatography (RPLC) for recognition, separation and identification of target components from Traditional Chinese Medicines (TCMs) Radix Caulophylli. The HEK 293 α1A cells with high expressing α1A adrenergic receptors were used to prepare the stationary phase in the CMC model. Retention fractions on the α1A AR–CMC model were collected using an automated fraction collection and injection module (FC/I). And each fraction was analyzed by RPLC under optimized conditions. 5-Methylurapidil (5-MU) and tamsulosin hydrochloride were used as standard compounds to investigate the suitability and reliability of the HEK 293 α1A AR–CMC–RPLC method prior to screening target component from Radix Caulophylli total alkaloid. The results indicated that caulophine was the target component acting on the α1A AR. This method could be an efficient way in drug discovery using natural medicinal herbs as a source of novel compounds.