To determine whether Hispanic and African-American patients are treated by cardiac surgeons with better or worse risk-standardized outcomes than surgeons of white patients, clinical data from the Massachusetts Data Analysis Center Registry were analyzed on all patients who underwent isolated coronary artery bypass grafting (CABG) from 2002 to 2004 by surgeons who performed >10 operations. Surgeons were divided into 4 groups based on their risk-standardized 30-day all-cause mortality incidence rates (top decile, top quartile, bottom quartile, and bottom decile). A total of 12,973 isolated CABGs were performed by 56 surgeons for 11,800 whites (91%), 413 Hispanics (3.2%), and 251 African- Americans (1.9%). White patients were more likely to be treated by surgeons in the top decile than by surgeons in the bottom decile (odds ratio [OR] 1.37, 95% confidence interval [CI] 1.07 to 1.76). In contrast, Hispanic patients were almost 3 times more likely to be treated by surgeons in the bottom decile compared with the top decile (OR 2.85, 95% CI 1.82 to 4.47). Compared with whites, Hispanic patients were about 1/2 as less likely to be treated by surgeons in the top decile (OR 0.51, 95% CI 0.35 to 0.75). African-American and white patients were similarly likely to be treated by surgeons in the top- and bottom-quality performance groups. In conclusion, Hispanics undergoing isolated CABG in Massachusetts were more likely to be operated on by cardiac surgeons with higher risk-standardized mortality rates than by surgeons with lower rates.