The goals of this study were to explicate adult ADHD’s relations with personality at both the domain and facet levels and to examine its associations with other psychological symptoms. Community members (N = 294) completed measures assessing ADHD inattentive and hyperactive/impulsive symptoms, five-factor model personality domains and facets, and other internalizing and externalizing symptoms. Inattentiveness showed strong negative relations with conscientiousness and extraversion and strong positive relations with neuroticism; in contrast, hyperactivity/impulsivity related negatively to agreeableness, positively to extraversion, and weakly to neuroticism. Whereas inattentiveness emerged as a positive predictor of internalizing psychopathology—and depression in particular—hyperactivity/impulsivity related weakly to internalizing but more strongly to externalizing psychopathology. Thus, inattentive and hyperactive/impulsive symptoms showed differential relations with personality—at both the domain and facet levels—and with other psychological symptoms. These results demonstrate the value in examining ADHD’s relations with personality facets and with a wide range of psychopathology within the same study.