Sodium arsenate and Yeonlyeonggobon-dan (nianlinggubendan) extract (YGD), a herbal restorative were treated p.o. 20 mg/kg and 500 mg/kg, respectively, and concurrently to rats, and examined the biochemical parameters in blood. The values of white blood cell (WBC), red blood cell (RBC), hemoglobin (Hgb) and hematocrit (Hct) in each group did not show significant variance. The value of aspartate aminotrasferase (AST) of arsenic-treated group was increased for 2 weeks significantly while that of the group of concurrent administration with YGD became low significantly compared with arsenic-treated group and the value of alkaline phosphatase (ALP) of arsenic-treated group was decreased while that of the group of concurrent administration with YGD was increased significantly compared with arsenic-treated group. In arsenic-treated groups, the value of glucose (Glu), and those of lactic dehydrogenase (LDH), blood urea nitrogen (BUN) and triglyceride (TG) were decreased at first but increased later while the groups of concurrent administration with YGD showed significant recovery from the toxicity of arsenic.