Evidence supports the role of temperament in the origins of psychiatric disorders. However, there are few data on associations between temperament and psychiatric disorders in early childhood. A community sample of 541 three-year-old preschoolers participated in a laboratory temperament assessment, and caregivers were administered a structured diagnostic interview on preschool psychopathology. In bivariate analyses, temperamental dysphoria and low exuberance were associated with depression; fear, low exuberance, and low sociability were associated with anxiety disorders; and disinhibition and dysphoria were associated with oppositional defiant disorder. Although there were no bivariate associations between temperament and attention-deficit/hyperactivity disorder, disinhibition emerged as a unique predictor in multivariate analyses. Findings indicate that the pattern of relations between temperament and psychopathology in older youth and adults is evident as early as age 3.