: Background and Objective: Saussurea lappa is a medicinal plant that has been used in the treatment of various disease conditions for decades. Researchers have provided diversified characteristics of this medicinal plant, enormous data about the bioactive compounds and as well its pharmacological properties. However, information regarding toxicity study of Saussurea lappa root is lacking. The acute and sub-chronic toxicity of Saussurea lappa root ethanolic extract was investigated in this study using an in vivo model (male Wistar rats). Materials and Method: The acute toxicity study was done in two phases: Phase One comprised four groups of three rats each which were administered with 50 mg, 100 mg and 1600 mg per kg bodyweight ethanolic extract of S. lappa while the last group (control) was given water and normal fed once. Phase Two involved administering 1600 mg, 2900 mg and 5000 mg per bodyweight. The median lethal dose of the plant was determined in the acute toxicity study. In sub-chronic toxicity studies, the effects of S. lappa root ethanol extract in daily single oral administration at the doses of 200, 400 and 800 mg/kg during 28 days were determined. The blood haematological and biochemical parameters as well as the histopathological examination of the liver and kidneys were studied. Results: In acute study, a single administration of the Saussurea lappa root ethanolic extract up to a dose of 5000 mg/kg did not cause mortality of animals all through the study. Thus, the median lethal dose (LD50) of Saussurea lappa root ethanolic extract was greater than 5000 mg/kg. Saussurea lappa root ethanolic extract caused no significant effect in the haematological and biochemical parameters of the treated groups when compared to the control. There were also no noticeable histological changes in the liver and kidneys of the Saussurea lappa treated rats compared to controls.. Conclusion: These results have shown that oral administration of Saussurea lappa root ethanol extract did not yield any significant toxic effect when acutely and daily administered for 28 days in the male Wistar rats. Hence, Saussurea lappa root ethanol extract could be regarded as a safe natural product for therapeutic use.