This study evaluated the effect of functional health status on mortality in a sample of community-dwelling older people. White and African-American self-respondents to the 1986 National Health Interview Survey Functional Health Supplement (n = 5, 320) were included in the study. Functional health status was measured by a ten-item unidimensional activities of daily living-instrumental activities of daily living (ADL-IADL) scale and a three-item cognitive ADL scale. Proportional hazards regression was used to evaluate the effect of increasing score on the ten-item ADL-IADL scale on risk of mortality over a 5-year period while controlling for demographic, social, and health status covariates. In both men and women, increasing score on the ADL-IADL scale was predictive of mortality, adjusting for increasing age, poor self-rated health, low body mass index in women, and being an unmarried man. These findings indicate that a unidimensional scale consisting of both ADL and IADL items is useful in predicting mortality, controlling for the effect of covariates in sex-specific models.