This study was designed to evaluate a repeated oral dose toxicity and immunomodulating activity of Pulsatilla koreana and Artemisiae annuae in Sprague-Dawley rats. The female rats were treated with Pulsatilla koreana and Artemisiae annuae of control group, low group (0.5 ml/kg), medium group (1 ml/kg), high group (2 ml/ kg) for distilled water, intragastrically for 4 weeks, respectively. To ensure the safety of Pulsatilla koreana and Artemisiae annuae such as the following were observed and tested. We examined the body weight, the feed intake, the clinical signs, the ophthalmological test, the hematological and the serum biochemical analysis. We also observed the histopathological changes of liver and kidney in rats. Hematological results were the increase of neutrophils, lymphocytes and monocytes in the high dose group of Pulsatilla koreana. The increase immune cells in the high dose group of Pulsatilla koreana might immunomodulating activity. No significant differences in body weight, feed intake, serum biochemical analysis and histopathological between control and fed group were found. In conclusion, Pulsatilla koreana and Artemisiae annuae is physiologically safe and improve immunomodulating activity.