Abstract: OBJECTIVE To establish a simultaneous determination method of three ephenrine alkalorids in Ephedra sinica Stapf. and its preparations by HPLC. METHODS The contents of three ephenrine alkalorids in Ephedra sinica Stapf., Jinmaxing Zhike Tables and Maxing Zhike Tables were determinated using a mixture of acetonitrile, methanol and 0.1% phosphoric acid(1.5∶4∶94.5) as the mobile phase by HPLC. RESULTS The methodological study showed that a good linear correlation existed in the range 0.102 9-0.686 μg(r=0.999 9) for ephedrine hydrochloride, 0.025 11-0.167 4 μg(r=0.999 6) for pseudoephedrine hydrochloride and 0.022 23-0.148 2 μg(r=0.999 9) for methylephedrine hydrochloride, respectively. The average recovery of ephedrine hydrochloride, pseudoephedrine hydrochloride and methylephedrine hydrochloriden was 100.56%, 97.84% and 98.42%, respectively. The RSD values were 0.20%, 0.94% and 1.31%(n=6), respectively. CONCLUSION The determination method of three ephenrine alkalorids can be used for the comprehensive evaluation on the quality of Ephedra sinica Stapf. and its preparations.