Objectives : Boo-ja and Cheon-o are not commonly prescribed, but are necessary for some clinical conditions, dispite the fact that some negative effects have been known to occur with these medicines. Hence, consequences for aspartate aminotransferase(AST), alanine aminotransferase(ALT) due to herbal medicines, including boo-ja and cheon-o are here reported. Methods : From January 2005 to July 2005, results were analyzed for 36 inpatients belonging to the sixth internal medicine department of Dongeui Oriental Medical Hospital who took herbal medicine, including boo-ja and cheon-o, over 20 days. The study is about the comparison and the investigation of LFT, and all results were taken upon their hospitalization and upon their departure. The standard of liver injury was used as a standard for their examinations. Results were as follows : No Change in normal limit : 28 of the 36 Increased AST. ALT from when they were hospitalized : 2 of 36 Normalized AST. ALT from when they were hospitalized with results higher than normal : 6 of 36 These results show no side-effects, therefore suggest that these herbal medicines, including boo-ja and cheon-o, do not cause adverse side-effects for patients of this kind if administered as was done in this study.