There is an increasing burden of obesity and obesity-related noncommunicable diseases in Gulf Cooperation Council countries, including Oman. This descriptive, epidemiological study assessed physical activity among 2977 Omani adults using a population-based household survey in 2008. Overall, 54.2% of men and 41.6% of women were physically active; the rate was higher in younger cohorts and varied significantly by region of residence. Physical activity related to the transportation (walking and cycling) domain was higher than in the leisure or work domains. Unmarried men aged 30–39 years were twice as likely to be physically active (OR 2.25) and unmarried women aged 40+ years were half as likely to be active (OR 0.58) than their married counterparts. Young women not working were less active (OR 0.18) than working women. Higher education was significantly associated with leisure activity for men aged 30+ years and women aged 40+ years. Further research to understand regional variations and to identify culturally appropriate strategies to promote physical activity is required.