A measurement model of mental health for the Older Americans Resources and Services (OARS) questionnaire is described. Using confirmatory factor analysis on noninstitutionalized elderly from Cleveland (N = 1834) and Virginia (N = 2146), the 21 OARS mental health items were fit to a 15-item model. In addition to the second-order construct of mental health, there were four first-order dimensions: life satisfaction, psychosomatic symptomatology, alienation, and cognitive deficit. Analyses were further replicated by splitting both samples in half. The model fit well and compared favorably to other alternative specifications. In addition to this analysis of internal structure, the model was also examined in relation to several exogenous factors including age, sex, race, education, and physical health. While the model again fit well, a model with cognitive deficit separate from the other factors seemed more reasonable.