Abstract: OBJECTIVE To isolate and identify the triterpenoid ginsenosides in fresh Ginseng Radix et Rhizoma by UHPLC-HRMS/MS, and to compare the differences of ginsenoside in different parts of Ginseng Radix et Rhizoma(main root, lateral root, fibrous root, and reed head). METHODS Water-saturated n-butanol was used as extraction solvent. Water-acetonitrile was used as the mobile phase for gradient elution. UHPLC-Q-Exactive Orbitrap MS/MS method for the analysis and characterization of ginsenosides in Ginseng Radix et Rhizoma was established in ESI negative ion mode, and the high resolution mass spectrometry data of each sample were collected. Combined with chromatographic retention behavior, accurate molecular weight, fragmentation law of multistage mass spectrometry and comparison of reference substances, ginsenosides in each sample were identified, and the differential peaks were screened to clarify the differences of different parts in Ginseng Radix et Rhizoma according to the relative content changes of identified ginsenosides in chromatography. RESULTS A total of 68 ginsenosides were detected from different parts of fresh Ginseng Radix et Rhizoma, including 44 in main root, 47 in lateral root, 52 in fibrous root and 37 in reed head. CONCLUSION There are great differences in ginsenosides in different parts of fresh Ginseng Radix et Rhizoma. Non-main medicinal parts such as ginseng lateral roots and reed heads, containing a large amount of ginsenosides and ingredients that are not detected in other parts, can be used as an important raw material for drug research and development and as a raw material for the extraction of various ginsenosides.