Abstract: Objective: To observe the clinical effect of Quyu Xingnao Decoction for vascular cognitive impairment no dementia (VCIND) after ischemic stroke. Methods: A total of 124 cases of VCIND patients with binding of phlegm and stasis syndrome after ischemic stroke were selected and divided into the Quyu Xingnao Decoction group and the control group according to the random number table method , with 62 cases in each group. During the treatment period, two cases were excluded from the Quyu Xingnao Decoction group and six cases were excluded from the control group. Finally,60 cases were included in the Quyu Xingnao Decoction group and 56 cases were included in the control group. The control group was treated with western medicine combined with cognitive function training,and the Quyu Xingnao Decoction group was treated with Quyu Xingnao Decoction based on the treatment of the control group. Both groups were treated continuously for four weeks. The clinical effects, Montreal Cognitive Assessment Scale (MoCA) scores,hemorheological indexes,and levels of S100 calcium-binding protein B (S100β) ,neuron specific enolase (NSE) and brain-derived neurotrophic factor (BDNF) in serum were compared between the two groups. Results:After treatment,the total effective rate was 96.67% in the Quyu Xingnao Decoction group, higher than that of 83.93% in the control group, the difference being significant (P<0.05). The MoCA scores in the two groups were increased when compared with those before treatment, and the MoCA score in the Quyu Xingnao Decoction group was higher than that in the control group, differences being significant (P<0.05). The levels of plasma viscosity, hematocrit, and fibrinogen (FIB) in the two groups were decreased when compared with those before treatment,and the levels of plasma viscosity, hematocrit, and FIB in the Quyu Xingnao Decoction group were lower than those in the control group, differences being significant (P<0.05). The levels of S100β and NSE in serum in the two groups were decreased when compared with those before treatment,and the serum BDNF levels were increased when compared with those before treatment, differences being significant (P<0.05); the levels of S100β and NSE in serum in the Quyu Xingnao Decoction group were lower than those in the control group, and the serum BDNF level was higher than that in the control group, differences being significant (P<0.05). Conclusion:Quyu Xingnao Decoction can effectively improve the cognitive function of VCIND patients with binding of phlegm and stasis syndrome after ischemic stroke, and its mechanism may be related to improving hemorrheology and repairing damaged neurons.