Shenfu Tang and Dushen Tang (one of the composite medicines for Shenfu Tang) are widely used Traditional Chinese herbal formulations and ginsenosides are their main bioactive components. However, there are rare studies about simultaneous analysis of ginsenosides in Shenfu Tang and Dushen Tang. In order to identify ginsenosides in Shenfu Tang and Dushen Tang and to explore law of compatibility of medicines in the decoction, a method for simultaneous determination of twelve ginsenosides in Shenfu Tang and Dushen Tang was developed by ultraresolution liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS). The method showed satisfactory linearity (r > 0.9915), repeatability (RSD < 9.58%), intra- and interday precisions (RSD<11.90%), and high yields of recovery (92.26-113.20%) for twelve major constituents, namely, ginsenosides-Rb1, Rb2, Rb3, Rc, Rd, Rg1, Re, Rf, Rg2, Rg3, Rh1, and F2. Furthermore, the concentration of twelve ginsenosides in Dushen Tang and Shenfu Tang was also simultaneously analyzed. Most of ginsenosides except Rg1 and Rb1 showed higher contents in Shenfu Tang compared to Dushen Tang. The compatibility of the formula had the effect of promoting or inhibiting the dissolution of some major components. The present research provided a reliable evidence for the illustration of chemical basis and compatibility regularity of Shenfu Tang. This study demonstrated the utility of the developed method for assessment of the quantity of the major constituents in Dushen Tang and Shenfu Tang.