In the present study, the anti-inflammatory effect of Haepyoejin-tang plus antler water extract was tested in formalin-injected chronic inflammation model in mouse hind paw. The test articles-100, 250, 500 mg/kg- were dosed once a day for 10 days, and changes on the body weight, paw weights were observed with histopathology of induced paw dorsum pedis. In addition, histomorphometry was also monitored at sacrifice. 15 mg/kg/10 mL of dexamethasone (DEXA) and diclofenac (DICLO) intraperitoneally dosed groups were used as reference groups. A significantly decrease of both absolute and relative paw weights were observed in all dosing groups including DEXA and DICLO groups compared to that of control, and a significantly decrease of the differences between intact and induced paw weights were also observed Haepyoejin-tang plus antler dosing groups compared to that of control. These histological signs-hypertrophy of paw dorsum pedis tissues were detected results from edematous changes on the cutaneous and subcutaneous tissues with severe infiltration of chronic inflammatory cells-were dramatically decreased in all dosing groups including DEXA and DICLO dosing groups compared to that of control. Especially, dose dependently decreases were detected in Haepyoejin-tang plus antler dosing groups compared to that of control. Base on these aforementioned results, it is concluded that Haepyoejin-tang plus antler have clear anti-inflammatory effect on the chronic inflammation induced by formalin injection.