Objective To establish a method of high performance liquid chromatography（HPLC）-tandem mass spectrometry determining the content of stachydrine hydrochloride from Motherwort granule. Methods The chromatographic conditions were Agilent SB-C18column（50 mm×2.1 mm,1.8 μm）,acetonitrile to 0.2％glacial acetic acid（70︰30）as the mobile phase,and a flow rate of 0.3 ml/min.Positive ion electrospray ionization（ESI＋）was applied for mass spectrometric detection under multiple reaction monitoring（MRM）mode.The monitored ions（m/z）was 144/58,144/84 respectively. Results The concentration of stachydrine hydrochloride being within 0.2 μg/ml to 10.0 μg/ml had a good linear relationship with the peak area.The r value was 0.9992,and the average recovery was 102.6％and the value of RSD was 1.5％（n＝6）. Conclusion The method is fast,simple,specific,and accurate in outcome,which can be used for quality control of Motherwort granule.