Epidemiological and clinical studies have shown an association between migraine and RLS [23–28]. However, the difference in the age-dependent prevalence of the 2 disorders suggests that the association may differ by age. However, the association of migraine and RLS in different age groups has yet not been determined. We therefore sought to investigate the association between migraine and RLS according to age groups using Korean Headache-Sleep Study data, a nationwide population-based study regarding headache and sleep disorders. A secondary outcome was to evaluate RLS prevalence according to the frequency of migraine headaches in order to corroborate the association of 2 disorders.