An ultra high performance liquid chromatography coupled to triple quadrupole mass spectrometry (UHPLC-QQQ-MS/MS) method has been developed to evaluate the quality of a pharmaceutical herbal preparation, Guanjiekang (GJK), through a simultaneous determination of 13 major active compounds with a huge difference in level of content. Chromatographic separation was achieved on a Waters Acquilty UPLC C18 column (2.1×100mm, 1.7μm) with a mobile phase consisting of acetonitrile and buffer solution (10mM ammonium acetate containing 0.1% acetic acid) under a gradient elution manner. A triple quadrupole mass spectrometer was operated in positive ionization mode with multiple reaction monitoring for the detection of the 13 compounds. All calibration curves showed excellent linear regressions (R(2)>0.999) within the test range. The precision, repeatability and stability of the 13 compounds were below 5.0% in terms of RSD. The recoveries were 99.2-103.9% with RSD of 0.23-3.30% for GJK samples. The method was successfully used for the analysis of samples of GJK preparation and showed that the lowest level was in aconitine (0.582±0.143ng/g) and the highest was in paeoniflorin (16.80±0.886mg/g), with a 41800 folds of difference. In conclusion, a rapid, sensitive, precise, accurate, and reliable UHPLC-QQQ-MS/MS method has been developed for the simultaneous detection of 13 active compounds with massive difference in level of content in the pharmaceutical samples of GJK preparation, which can be applied for the quality control of GJK product.