To evaluate the safety of Yizhi Qingxin Formula(YQF) by investigating the acute toxicity and death within 24 h after oral gavage of YQF，so as to provide reference for further study on repeated dose toxicity and clinical medication in practice.Methods:ICR mice(24 to 33 g)，including equal numbers of male and female mice，were randomly divided into the YQF group and the blank control group.With the maximum dose method，an equal volume of YQF solution and pure water were given by oral gavage twice a day，based on the maximum gavage volume of 40 mL/kg.The general condition and body weight of the mice were monitored regularly during the oral administration period.After 14 days，blood and urine samples were collected，and gross anatomy was conducted to evaluate the effects of YQF on organ coefficient and routine blood and urine test results.Results:The ICR mice were orally administered by 40 mL/kg twice a day with YQF at a maximum concentration of 0.36 g dry extract/mL.The cumulative dose was 98.6 g crude drug/kg body weight，which was about 298 times(calculated by body weight in kilogram) and 38 times(calculated by body surface area) the proposed dose in adults.No toxicity-related symptoms and death of mice were observed in both groups.There was no statistical significance in body weight，organ coefficient，and routine blood and urine test results between the YQF group and the control group(P>0.05).Conclusion:Under the conditions of this study，no significant acute toxicity and death were observed in the experiment on the single dose acute oral toxicity of YQF in mice，showing its maximum tolerated dose was greater than 98.6 g crude drug/kg body weight.