Prostate cancer survival varies markedly by ethnicity. American Indians and blacks have the lowest 5-year relative survival among ethnic groups in the U.S. In New Mexico, relative survival for prostate cancer is lower for ethnic minority groups than for non-Hispanic whites. To examine factors underlying ethnic differences in prostate cancer survival in New Mexico, we analyzed Surveillance, Epidemiology, and End Results Program data collected by the New Mexico Tumor Registry from 1983 to 1992. Unadjusted relative risk (RR) of death after prostate cancer diagnosis was greater for Hispanics [RR = 1.1; 95% confidence interval (CI), 1.0, 1.2], American Indians (RR = 1.4; 95% CI, 1.2, 1.5), and blacks (RR = 1.5; 95% CI, 1.2, 1.7) than for non-Hispanic whites. After adjusting for age, stage, histological grade, year of diagnosis, and initial treatment, the risk for Hispanics (RR = 1.0; 95% CI, 0.9, 1.1), American Indians (RR = 1.0; 95% CI, 0.9, 1.1), and non-Hispanic whites was comparable. Although based on small numbers, adjusted risk ratios among blacks remained elevated (RR = 1.2; 95% CI, 0.9, 1.6), due in part to lower survival during the first 12 months after diagnosis (RR = 2.0; 95% CI, 1.2, 3.3) and poorer survival following radical prostatectomy (RR = 4.2; 95% CI, 1.3, 13). These findings suggest that poorer survival for Hispanics and American Indians may be explained by delayed detection and differences in treatment.