Objective：To analyze the distribution and frequency of clopidogrel related gene CYP2C19 polymorphism in patients with acute cerebral infarction in Zhangjiakou area of Hebei province. Methods: 249 patients with acute cerebral infarction admitted to the first affiliated Hospital of Hebei North University from September 2021 to March 2023 were selected. The exfoliated cells of oral mucosa were collected and CYP2C19 genotyping was detected by POCT method. The patients were divided into groups according to sex and age, and the distribution of CYP2C19 genotypes and clopidogrel metabolic types among the groups were compared. Results: Five genotypes were detected: fast metabolic CYP2C19*1/* 1 in 9 6 cases, accounting for 38.60%; CYP2C19*1/*2 in middle metabolic type, accounting for 45.00%, 1 0 cases, accounting for 4.00%; slow metabolic type, 25 cases, accounting for 10.00%, CYP2C19*2/*3, 6 cases, accounting for 2.40%. The frequency distributions of alleles * 1, * 2 and * 3 were 63.05%, 63.05% and 3.21%, respectively. No genotypes of CYP2C19*1/*17, CYP2C19*17/*17, CYP2C19*2/*17,CYP2C19*3/*17 and CYP2C19*3/*3 were detected in this study. There was no significant difference in sex, genotype and metabolic type distribution frequency (P>0.05). There was no significant difference in age, genotype and metabolic type distribution frequency (P>0.05). Conclusion: The CYP2C19 polymorphism of clopidogrel related gene in patients with acute AIS in Zhangjiakou area of Hebei Province is mainly middle metabolic type, and the middle and slow metabolic type accounts for 61.40%. Most people have platelet hyperresponsiveness, so gene detection is carried out before medication to develop a safe, reasonable, effective and economical personalized drug treatment plan.