This study aims to compare the chemical composition differences between fresh and dried Pheretima aspergillum produced in Guangdong and to establish quality evaluation standards by determining the contents of hypoxanthine,xanthine,and uracil.Ultra-performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS) was used to analyze the primary chemical components in both fresh and dried samples,while high-performance liquid chromatography (HPLC) was employed to quantify the levels of hypoxanthine,xanthine,and uracil.The results indicated that,based on comparisons with databases established from literature and laboratory work,56 compounds were identified in the dried samples,including 11 free amino acids,16 organic acids,9 nucleosides,9 dipeptides and cyclic dipeptides,and 11 nitrogen-containing and miscellaneous compounds.In the fresh samples,48 compounds were identified,including 11 free amino acids,17 organic acids,10 nucleosides,8 dipeptides and cyclic dipeptides,and 2 nitrogen-containing and miscellaneous compounds.The separation of hypoxanthine,xanthine,and uracil was achieved with satisfactory results,exhibiting good linearity within the calibration range (r=0.999 9).The average recovery rates ranging were between 98.36% and 99.82%,and the relative standard deviations were between 0.25% and 3.1%.The UPLC-Q-TOF-MS/MS technique used in this study provided a rapid and efficient qualitative analysis method for identifying the chemical components in both fresh and dried Pheretima aspergillum samples.The HPLC method developed is simple,fast,and accurate for quantifying hypoxanthine,xanthine,and uracil.This research provides a scientific basis for studying the chemical composition and quality control of fresh and dried Pheretima aspergillum.