Abstract: A method of fluorescent spectrometry was developed for the determination of berberine hydrochloride, based on the sensitization effect of sodium dodecyl sulfate (SDS) on the fluorescence of berberine hydrochloride. In the buffer solution of Tris-HCl with pH of 7.0, berberine hydrochloride reacted with SDS solution (0.01 mol·L-1) for 15 min and the system displayed the maximum fluorenscence intensity at 530 nm. A linear relationship was found between the fluorescence intensity and the concentration of berberine hydrochloride in the range of 1.0-10 mg·L-1, with detection limit (3s/k) of 0.23 mg·L-1. The method was applied to the determination of berberine hydrochloride in pharmaceutical preparations, giving results consistent with that obtained by the pharmaceutical law. Recovery rates obtained by standard addition method were in the range of 94.9%-106% and RSDs (n=6) were in the range of 1.9%-3.7%.