Migraine is a primary headache disorder with a prevalence of 11.6% globally and 27% in Saudi Arabia. Irritable bowel syndrome (IBS) has a prevalence of 9.2% worldwide. The prevalence of IBS has not been established nationally. However, provincial studies for migraine and IBS have been conducted nationwide. There is a significant link between migraine and IBS globally. Migraineurs had a considerably greater prevalence of IBS than nonmigraineurs (OR = 2.49, 95% CI 2.22-2.78). Patients with IBS have 60% higher odds for migraines. This identifies an association that needs to be investigated in a nationwide manner. The study has two main aims. The first is to measure the prevalence of migraine and irritable bowel syndrome in Saudi Arabia. The second is to observe the association and the relationship between migraine and irritable bowel syndrome in Saudi Arabia. A cross-sectional study was conducted among the general population of Saudi Arabia between March 2021 and June 2021, whose ages are 15 years old or greater. Participants filled an online self-administered survey. The data collection tools included the Migraine Screen Questionnaire (MS-Q) for migraine symptoms, migraine severity (MIGSEV) scale for severity of migraine, and the IBS module of the Rome IV Diagnostic Questionnaire (R4DQ) for IBS symptoms and their subtype. With 2802 participants, the majority of the study samples were males, who constituted 52.5%. Among the study's sample, the prevalence of migraine consisted of 27.4%, and the prevalence of IBS was 16.4%. The odds of having IBS in migraineurs were much higher than in those without migraine (OR 4.127; 95% CI 3.325-5.121), and the association was statistically significant (p < 0.001). In conclusion, there is a strong association between migraine and irritable bowel syndrome in Saudi Arabia.