This retrospective cohort study evaluated associations of race/ethnicity and gender with outcomes of diabetes complications severity, health care resource utilization (HRU), and costs among Medicare Advantage health plan members with type 2 diabetes (T2DM). Medical and pharmacy claims were evaluated for 333,576 members continuously enrolled from January 1, 2010, to December 31, 2011, aged 18-89 years, with ≥1 primary diagnosis medical claim, or ≥2 claims with a secondary diagnosis of T2DM (International Classification of Diseases, Ninth Revision, Clinical Modification code 250.x0 or 250.x2). Complications severity assessment by Diabetes Complications Severity Index ranged from 0 (no complications) to 5+. Mean (SD) all-cause medical, pharmacy, and total costs were reported alongside all-cause HRU by place of service (outpatient, inpatient, emergency room [ER]) and number of visits. Multivariate regression showed being Hispanic, black, or male was associated with higher prevalence of more severe complications. This racial/ethnic disparity was more pronounced among females, among whom odds of having more severe complications were higher for Hispanic and black as compared to white females [(Hispanic vs. white odds ratio [OR], 1.40; 95% confidence interval [CI], 1.32-1.48), and (black vs. white OR, 1.22; 95% CI, 1.19-1.25)]. Regardless of gender, blacks had more ER visits than whites. White females incurred the highest total health care costs (mean annual costs: $13,086; 95% CI, $12,935-$13,240, vs. Hispanic females: $10,732; 95% CI, $10,406-$11,067). These effects held regardless of other demographic and clinical attributes. These findings suggest racial/ethnic and gender differences exist in certain T2DM clinical and economic outcomes.