Serum lipids are correlated with certain types of cerebrovascular atherosclerosis. The -1131T>C polymorphism in apolipoprotein A5 (APOA5) is associated with triglyceride levels. We investigated associations among this polymorphism, triglycerides, and stroke in 160 cases of acute ischemic stroke or transient ischemic attack and 157 healthy control subjects. Both patients and controls were Chinese. The APOA5 polymorphism was significantly associated with triglyceride levels both in patients and controls. The average triglyceride level was 70% greater in patients and 92% greater in controls with CC than with TT genotypes. Logistic regression indicated that triglyceride level was an independent risk factor for ischemic stroke in this population. However, APOA5 genotypes were not significantly associated with strokes or stroke subtypes, though larger studies would be needed to exclude the possibility of a small effect on stroke risk.