Background: Hypertension is a significant global public health problem and the data suggest a wide health disparity in hypertension prevalence worldwide. Our objective was to assess some epidemiological determinants in individuals ≥ 50 years influencing blood pressure/hypertension in United States and Croatia and derive some meaningful conclusions and recommendations. Material and methods: We used the American National Health and Nutrition Examination Survey (NHANES) (n = 1,556; 48.9% women) and the Croatian Adult Health Cohort Study (CroHort) (n = 2,182; 66% women), both taken in 2008. The health indicators compared were anthropometries, blood pressure, socioeconomic and marital status, education and lifestyle, including physical activity, alcohol and coffee consumption, smoking and presence of dyslipidemia and diabetes. Results: Prevalence of hypertension based either on medication use or blood pressure values was significantly higher in Croatian men and women compared to American (all p < 0.001). Waist circumference was the main positive predictor and education a negative predictor for blood pressure in CroHort; significance was not reached in NHANES, although the trends were similar. Taking medications for diabetes decreased the odds for hypertension in NHANES, while taking medications for both diabetes and dyslipidemia decreased the odds in CroHort. Conclusions: Croatian people older than 50 years have higher prevalence of hypertension compared to their counterparts in the U.S. The difference in the prevalence of hypertension in two populations cannot be explained by different prevalence of risk factors examined, except education level. Higher prevalence of hypertension diagnosed by medication use indicates a relatively good control of the disease in both populations.