AIM: To explore the value of adenosine triphosphate-binding cassette transporter B1 (ABCB1) G2677T gene polymorphism detection in lipid-lowering therapy with atorvastatin in patients suffered from ischemic stroke. METHODS: This study was a prospective study. 116 patients with ischemic stroke were recruited consecutively as subjects. The ABCB1 G2677T (rs2032582) gene polymorphism was detected by fluorescence staining in situ hybridization. According to the detection results, the patients were divided into GG genotype, GT genotype and TT genotype groups. All patients in the three groups were given atorvastatin 20 mg/d for lipid-lowering treatment. The changes of serum HDL-C, LDL-C, TC and TG levels in the three groups before and after treatment were compared by repeated measures analysis of variance. The serum LDL-C level<1.8 mmol/L was considered as the effective treatment for lowering blood lipid, and the difference of effective rate among the three groups was compared. The adverse drug reactions of the three groups were recorded. RESULTS: There were 47 (40.5%), 43 (37.1%) and 26 (22.4%) patients in GG genotype, GT genotype and TT genotype groups, respectively. There was no significant difference in serum TC, TG, HDL-C and LDL-C levels among the three groups before treatment (P>0.05); After treatment, the levels of serum TC, TG and LDL-C in the three groups were lower than those before treatment, and the levels of HDL-C were higher than those before treatment, and there was a trend of change with treatment time (FTC=77.780, P<0.001; FTG=14.218, P<0.001; FLDL-C=105.106, P<0.001; FHDL-C=6.811, P=0.010); The interaction existed between different gene types of ABCB1G2677T and treatment time in serum LDL-C (F=3.604, P=0.030), and the change trend of serum LDL-C level with time was different in the three groups; There was no interaction between different gene types of ABCB1 and treatment time inserum TC, TG, HDL-C (FTC=2.545, P=0.083; FTG=0.585, P=0.559; FHDL-C=0.012, P=0.988), and the change trend of serum TC, TG, HDL-C levels with time was the same in the three groups. The decrease of serum LDL-C level in GG genotype group was 36.99% (16.03%, 50.13%), which was higher than 22.75% (12.43%, 41.11%) in GT genotype group and 16.66% (7.37%, 24.82%) in TT genotype group. The difference in the decrease of serum LDL-C level among the three groups was statistically significant (c2=11.630, P=0.003), and the decrease in GG genotype group was significantly higher than that in TT genotype group (P=0.002). The effective rate of lipid-lowering treatment in GG genotype group was 72.34%, higher than 44.18% in GT genotype group and 38.46% in TT genotype group. There was a statistically significant difference in the effective rate among the three groups (c2=10.565, P=0.005), and the effective rate in GG genotype group was significantly higher than that in TT genotype group (c2=8.024, P=0.005). The total incidence of adverse drug reactions in the three groups was similar (c2=1.649, P=0.438). CONCLUSION: The blood lipid lowering extent and effective rate of GG genotype patients with ABCB1 G2677T gene are higher than those of GT genotype and TT genotype patients. Detection of ABCB1 G2677T gene polymorphism has certain application value in the treatment of ischemic stroke patients with atorvastatin.