The Cancer Registry Division of the Texas Department of Health identified 349 malignant tumors among Anglo and Hispanic children and adolescents less than 20 years of age who lived in a southwestern region of Texas during the period 1976-1980. The ethnic distribution of cases consisted of 184 Anglos (53%) and 165 Hispanics (47%). The total cancer incidence rate per million for Anglos was 198.2 for males and 141.2 for females; for Hispanics the rate was 130.7 for males and 142.0 for females. The rates for all sites combined were higher for Anglo males than for US white (Anglo and Hispanic) males. Anglo females, Hispanic males, and Hispanic females had all sites combined rates that were similar to the rates for US white males and females. Anglo males were at increased risk for brain/central nervous system and kidney tumors. Leukemia was the most frequent cancer seen. All ethnic/sex groups were at increased risk for leukemia; however, only females had significantly higher rates.