This study was conducted to investigate the hematological changes of the dogs when administrated excessive amount of the Artemisia capillaris extract for a short period. In this experiment, clinically healthy dogs(n = 20, average weight = 7.68 kg) were divided into 2 groups : Artemisia capillaris rude juice extract group(CR) and concentrated extract group(CE). They were inserted stomach tube and administrated the extracts (5 ml/kg) for 8 days. The followings are the results of this experiment.: 1). The number of red blood cell(RBC) was significantly (p<0.05) decreased in CE group on day 4, 5, 6, whereas CJE group showed significantly (p<0.05) difference on day 5. 2). The packed cell volume(PCV) and hemoglobin concentration were significantly (p<0.05) decreased in both groups during experimental periods. 3). The met hemoglobin was significantly (p < 0.05) increased from 12 hrs after administration to day 8 in CJE group wheres, it was significantly (p<0.05) increased on day 6,7 in CE group.