Objectives : This study was carried out to investigate the effects of Jaeumgeonbi-tang extract on indomethacin-induced gastric mucosal lesions of mice. Methods : Experimental groups were classified into non-treatment group (CON group), non-administered group (GE group), misoprostol administered group (MA group) and Jaeumgeonbi-tang extract administered group (JG group). This study examined the morphological change, distribution of mast cells, mucous secreted cells and apoptotic cells, BrdU, COX-1, Hsp70, NF-κB p50, PKC, COX-2 and TNF-α of gastric mucosa. Results : 1. The hemorrhagic erosion of gastric mucosa and infiltrated mast cells were reduced in the MA and JG groups. 2. PNA reaction and mucous secreted cells were increased in the MA and JG groups. 3. The distribution of apoptotic cells, Hsp70, NF-κB p50, PKC, COX-2 and TNF-α were increased in the gastro­inflammation elicitated group, but decreased in the MA and JG groups. 4. The MA and JG groups showed increase on COX-1, BrdU. Conclusions : Jaeumgeonbi-tang extract had excellent effects on indomethacin-induced gastric mucosal lesions.