OBJECTIVES: Few studies have assessed racial/ethnic and gender differences in diabetes-related complications, healthcare resource utilization (HRU) and costs in patients with type 2 diabetes mellitus (T2DM).  This study explored the association of race/ethnicity and gender with complications severity, HRU, and costs among Medicare Advantage patients.    METHODS: A retrospective cohort study was performed using medical and pharmacy claims of 333,576 Medicare members enrolled from 1/1/2010 to 12/31/2011, aged 18 to 89, and with ≥ 1 medical claim with primary diagnosis or ≥ 2 medical claims with  secondary diagnosis of T2DM (ICD-9-CM 250.x0 or 250.x2).  Complications severity was assessed with the Diabetes Complications Severity Index, with scores of 0 (no complications) through 5+ (five or more).  HRU was reported by mean (standard deviation [SD]) number of outpatient, inpatient, and emergency room [ER] visits. Costs were reported as means (SD) of medical, pharmacy and total healthcare costs evaluated.  Associations of race/ethnicity and gender with the three outcomes were evaluated using generalized linear regression models. RESULTS: The sample was older (70.81 ±8.8 years) and 80% White.  Being Hispanic, Black, or male was associated with a higher prevalence of more severe T2DM complications; this disparity was more pronounced among females, with the odds of having more severe complications being higher for Hispanic and Black females compared to White females (Hispanic v. White odds ratio [OR], 1.40; 95% confidence interval [CI], 1.32-1.48), and (Black v. White OR, 1.22; 95% CI, 1.19-1.25). Regardless of gender, Blacks had more ER visits than Whites.  Whites, particularly females, incurred the highest total annual healthcare costs, (White female costs: $13,086; 95% CI, $12,935-$13,240) vs. (Hispanic female costs: $10,732; 95% CI, $10,406-$11,067).   CONCLUSIONS: Racial/ethnic and gender differences exist in certain T2DM clinical and economic outcomes.  Following these specific patients’ progress more closely may prevent or delay complications and decrease long term costs