Objective To study the safety of the Chang Wei Ning Capsule and to provide a reference for clinicalapplication. Methods Forty mice (males and females) were randomly divided into a Chang Wei Ning Capsule group and anormal control group, each containing twenty mice. Mice of the test group received 32 g/ kg body weight Chang Wei NingCapsule, while those of the control group received the same volume of pure water. A detailed observation of the mice,including examination of viscera morphology by naked eye, was conducted until day 14 post-drug administration. Onehundred and twenty rats (males and females) were randomly divided into a normal control group and three different ChangWei Ning Capsule dosage groups (9, 3, 1 g/ kg bodyweight). The rats received consecutive intragastric administrations ofChang Wei Ning Capsule over a 13-week period. In addition to observing the general condition of the animals, body weight,blood, hepatic function and renal function measurements, and a histopathology analysis, were performed after the 13 weektreatment duration and at four weeks-post drug withdrawal. Results No toxic reaction was observed in mice that receivedintragastric administrations of Chang Wei Ning Capsule (32 g/ kg). No abnormal reaction was also observed in the rats of alldosage groups that received intragastric Chang Wei Ning Capsule over a 13-week period. Conclusions The maximumadministered dose of Chang Wei Ning capsule in mice was 32 g/ kg body weight in a single-dose toxicity test. No observed adverse effects were observed in rats receiving up to 9 g/ kg drug per day in repeated-dose toxicity tests.