Objective To study the chronic toxicity and its severity of a Chinese medicine, Anshen Bunao Liquid (ABL), in rats, provide the target organs and extent of reversibility of their adverse effects, determine its non-toxic dose, and to evaluate the safety of medication and provide reference for clinical trial dose and observation indexes. Methods Two hundred and forty healthy 6-week old Wistar rats (male:female=1:1) were divided into low, middle, and high dose Anshen Bunao liquid groups (2.5, 5, 10 mL/kg), and solvent control group (distilled water 2 mL/100 g), with 60 rats in each group. The drug was orally administered to rats once a day and 6 days per week for 26 weeks. The general state, body mass and food intake were measured.By the end of 13 weeks, 26 weeks of experiment and 4-week recovery period after drug withdrawal, hematological and biochemical indexes were assayed, organ coefficients were determined, and histopathological observation was performed. Results Long-term continuous oral administration of Anshen Bunao liquid, the general state, behavior and gross appearance showed no significant abnormal changes. Compared with the control group, no significant differences in all checked items were found in the treatment groups.During 3 and 6 months, the size and location of organs, organ weight and organ coefficient had no obvious changes, with only non-significant increase of weight of some organs. All the organ coefficients of the animals in different groups were within normal range. Histopathology showed no obvious pathological and toxicological changes even in the high-dose drug treatment group, and no delayed toxicity occurred after withdrawal of drug administration. Conclusions The Chinese drug, Anshen Bunao liquid has no obvious toxicity and no delayed toxicity after withdrawal of the drug in rats. It is expected that the planned dose in clinical use is a safe dose.