Objective To investigate the relationship between platelet-activating factor acetylhydrolase gene Arg92His(4, 275; G→A), Ile198Thr(7, 593; T→C) and Val279Phe(9, 994; G→T) mutation and cerebral artery athero-sclerosis stenosis. Methods Six hundred forty-twopatients with cerebral infarction underwent cerebral digital subtrac-tion angiography (DSA).The patients were then divided into cerebral artery atherosclerosis stenosis (CAAS) group(n=477) and control group(n=81) accroding to the site and severity of their cerebral artery stenosis. Furthermore, the CAAS group were divided into intracranial artery stenosis(ICAS) subgroup(n=251), extracranial artery stenosis(ECAS) subgroup (n=115) and extracranial-intracerebral artery stenosis(ECAS) subgroup(n=111). The distributions of genotype and allele frequencies of Arg92His,Ile198Thr and Val279Phe mutation of platelet-activating factor acetylhydrolase gene were ex-amined and comparied in different groups. Results There were significant differences in the distributions of genotype and allele of Arg92His mutation between ICAS subgroup and control group(42.6% vs. 30.3%;23.3% vs. 16.4%, P <0.05). These associations were not detected in ECAS and IECAS subgroups. There was no significant association be-tween Ile198Thr and Val279Phe and stenosis at any site(P>0.05). The distributions of genotype and allele of Arg92His, Ile198Thr and Val279Phe mutation were no significantly difference between CAAS group and control group (P >0.05). Conclusions Arg92His mutation may be associated with intracranial artery atherosclerotic stenosis.