Objectives.—The aim of this study is to evaluate endothelial function in migraineur subjects during the asymptomatic period. Background.—Migraine has been proposed as a risk factor for cerebrovascular events. The underlying mechanisms that relate these 2 pathologies are unknown. Nitric oxide (NO) has been proposed as the final causative molecule of migraine. Increased NO metabolites concentrations have been reported in migraineur subjects during acute migraine attacks, but there is no evidence indicating alterations in endothelial NO release during the symptom free period in theses subjects. Design and Methods.—Fifty migraineur subjects and 25 healthy subjects matched by gender and age were included. Every subject underwent a complete examination that included medical history, physical examination, resting electrocardiogram, forearm flow‐mediated vasodilation (FMD), blood determinations of fasting nitrates and nitrites (NO 2 − + NO 3 − ), glucose, lipid profile, creatinine, C‐reactive protein, and blood cell count. Results.—No differences in FMD or NO 2 − + NO 3 − were detected among groups. The only difference between migraineurs and control subjects was a higher mean blood pressure 92.1 (8.8) mmHg versus 86.7 (8.2) mmHg P = .01. Conclusion.—The endothelial function is not altered during the interictal period in migraineur subjects.