Objectives: This study was performed to identify temperament and character factors in children and adolescents with attention deficit hyperactivity disorder(ADHD) according to diagnostic subtypes, which were assessed using the Kiddie-Schedule for Affective Disorders and Schizophrenia-Present and Lifetime Version(KSADS-PL). Methods: Ninety subjects with ADHD(72 males, 10.07±2.73 years) were diagnostically assessed with the KSADS-PL given separately to mothers about their children and to children about themselves. The JTCI was applied to measure temperament and character factors. Separate JTCI data were obtained from mothers about their children and from children about themselves. Basic demographic data were also obtained. Results: More girls were diagnosed as predominantly inattentive type of ADHD(p=.048). Even after adjusting the influence of sex, combined and predominantly hyperactive-impulsive type of ADHD group showed higher Reward Dependence(p<.001) and Persistence(p=.007), and lower Self-Directedness(p=.048) and Cooperativeness(p=.004), and younger age(p=.038) than predominantly inattentive group. Conclusion: Temperament and character factors were significantly associated with ADHD subtypes.