Mexican-Americans are disproportionately burdened by metabolic syndrome, a medical condition characterized by the concurrence of clinical abnormalities that contributes to diabetes, obesity, and cardiovascular disease (CVD). This is alarming since Mexican-Americans constitute two-thirds of the US Latino population, the largest minority and fastest growing group in the US. Investigating acculturative stressors associated with immigration is crucial for eliminating health disparities, but few studies have examined the acculturative impact of Mexican migration to the United States or the relationship between acculturation and metabolic syndrome among Mexican-Americans. The purpose of this dissertation research was to investigate the associations between acculturation and metabolic syndrome among a bi-national sample of Mexicans and Mexican-Americans. Metabolic syndrome was assessed among a bi-national sample of individuals with diabetes using the definition outlined by the International Diabetes Federation, and acculturation was assessed by proxy measures (years lived in the US and generational status) and responses on the Acculturation Rating Scale for Mexican-Americans, version-II. Chi-square, analysis of variance, and logistic regression were used to determine relationships between country, gender, and acculturation status and metabolic syndrome and its biomarkers. The overall prevalence of metabolic syndrome was 79.7%, with 85.0% prevalence among Mexican-Americans and 75.7% among Mexicans (p=0.069). Mexican-Americans had higher blood pressure and central obesity, while Mexicans had higher triglycerides levels. The majority (81.2%) of Mexican-Americans was first generation and lived in the US for an average of 27.65 +/- 16.05 years. The mean acculturation score was -1.83 +/- 1.56, which indicated participants in this study were Mexican-oriented, or more closely associated to Mexican cultural influences than Anglo cultural influences. Higher acculturation scores were positively associated with fasting blood glucose and systolic blood pressure and lower acculturation was negatively associated with fasting blood glucose. Logistic regression analysis showed first generation Mexicans-Americans were more likely to develop metabolic syndrome than second generation Mexican-Americans (OR 7.399, 95% CI 1.464-37.401, p=0.015). Mexican and Mexican-American individuals with type 2 diabetes have a high prevalence of metabolic syndrome, which increases their risk for heart disease and other cardiovascular complications. Mexican-Americans are especially affected by central obesity and hypertension and Mexican immigrants appear to be impacted by negative lifestyle factors upon entering the United States. Acculturation is a complex process and the unclear relationship between acculturation and metabolic syndrome warrants further investigations.