Most findings on associations of physical activity and sedentary behavior with the metabolic syndrome are from developed countries; thus, we examined these relationships in adults from Sur, Oman. The Sur Healthy Lifestyle Survey (n = 1,335) used the World Health Organization (WHO) Stepwise methodology to assess chronic disease risk factors. Odds ratios for the metabolic syndrome were estimated using logistic regression models for domains of physical activity (work, transport, and leisure) and sitting time, and adjusted for confounding variables. Compared to their counterparts doing the least physical activity, lower odds of the metabolic syndrome were observed among those with higher work activity (0.60; 95% confidence interval (CI): 0.45, 0.80) and transport activity (0.69; 95% CI: 0.47, 1.00), but not leisure activity (0.91; 95% CI: 0.64, 1.32). Odds of the metabolic syndrome were higher in those who sat for ≥6 h daily compared to <3 h daily (odds ratio = 1.60, 95% CI: 1.04, 2.44), but not after further adjustment for physical activity. This is the first evidence from the Arabian Gulf on associations of physical activity and sitting time with the metabolic syndrome and provides empirical evidence to inform national physical activity guidelines, policies and programs.