Abstract: The objective of this study is to investigate the permeabilities of rebamipide across the jejunal, ileal and colonic membranes in rat. The permeability (P_app) of rebamipide via rat intestinal membranes at concentration of 80 μmol·L^-1 was evaluated by an in vitro diffusion chamber system after the membranes were isolated from the rat intestine. And the concentration of rebamipide in the receptor was determined by HPLC. As a result, the permeability of rebamipide across the jejunal or ileal membrane was higher than that across the colonic membrane, and the permeability of rebamipide in the ileal tissue from the serosal to mucosal direction was greater than that from the mucosal to serosal direction. Therefore, there was a regional difference in the permeability of rabamipide across the jejunum, ileum and the colon in rat. Also, the transporters in the intestinal mucosa as p-glycoprotein may not be involved in the transport of rebamipide.