Objective,2,To observe the clinical effect of Yiqi Huayu Decoction on intracranial residual hematoma after burr hole drainage surgery of chronic subdural hematoma (CSDH).,Methods,2,A total of 56 patients with chronic subdural hematoma were randomly divided into treatment group (,n,=33) and control group (,n,=23). Both groups conducted burr hole drainage surgery. After surgery, the treatment group was treated with Yiqi Huayu Decoction, while the control group was treated with atorvastatin tablets. The two groups were administered corresponding medicine continuously for at least 4 weeks until the residual hematoma was completely absorbed or the volume significantly reduced (,V,≤10 cm,3,).,Results,2,①During the follow-up period, there were 2 dropout cases, including 1 case in the treatment group and 1 case in the control group. ②The differences in the volume of residual hematoma were significant (,P,<,0.05) when comparing the volume before operation and that at each time point after operation in both groups. The differences in the volume reduction rate of residual hematoma were significant statistically when comparing the reduction rate on day 7 after operation and that on day 14, day 30, day 60 and day 180 respectively after operation in both groups (,P,<,0.05). The volume of residual hematoma in the treatment group was significantly smaller than that in the control group on day 60 and day 180 after operation (,P,<,0.05), and the volume reduction rate of residual hematoma in the treatment group was significantly higher than that in the control group on day 30, day 60 and day 180 after operation (,P,<,0.05). ③During the follow-up period, the recurrence rates of residual hematoma in the treatment group and the control group were 3.1% (1/32) and 13.6% (3/22), respectively, with no significant difference (,P,>,0.05). ④Logistic regression analysis showed that the old age (,>,80 years old) and the smaller hematoma volume reduction rate after operation (,<,30%) were closely related to hematoma recurrence (,P,=0.008,P,=0.01). ⑤The modified Rankin score of the two groups decreased significantly before and after operation (,P,<,0.05). There was no significant difference in modified Rankin score between groups at each time point after operation (,P,>,0.05). ⑥There was no significant difference in the incidence of adverse reactions between the two groups (,P,>,0.05).,Conclusion,2,Compared with atorvastatin tablets, Yiqi Huayu Decoction can better promote the absorption of residual hematoma after burr hole drainage surgery in patients with chronic subdural hematoma. Meanwhile, without severe adverse reactions, Yiqi Huayu Decoction can also improve the postoperative neurological function of patients.