Abstract: The purpose of this study is to systematically investigate the characteristics of absorption and metabolism of oxymatrine (OMT) using rat intestinal perfusion model. Ultra performance liquid chromatography (UPLC) and high performance liquid chromatography-electrospray ionization-quadrupole-time of flight mass spectrometry (HPLC-ESI(+)-Q-TOF-MS) were used to test absorption of OMT in intestine at 100, 200 and 400 μmol·L^-1. The absorption rate and permeability of OMT is not dependent on concentration, but through passive absorption in intestine (P > 0.05). In the rat intestine, the absorbed amount of OMT was significantly different in four sections of the intestine in an order of duodenum > jejunum > ileum > colon (P < 0.05). OMT is metabolized into two metabolites in duodenum and jejunum, and matrine (MT) is the major one.