A questionnaire study was conducted on children with attention deficit disorder (ADD) in order to clarify their problems of adaptation in daily and school life, and to note the differences in their maladaptation according to their age. Questionnaires concerning daily life were mailed to the parents of 157 children diagnosed as ADD at the Kochi Prefectutural Mental Health Center between 1973 and 1982. Sixty-nine parents replied. Questionnaires concerning school life were mailed to 57 teachers of ADD children, who had previously received the parents permission to respond to these quesionnaires. Forty teachers sent back replies. The subjects were divided into 2 or 3 groups according to their age. In daily life, the number of children capable of coordinated motions, shopping by themselves and playing a role in games, was greater in the high-age group than in the low-age group. Hyperactivity was not observed among the school children, and this was attributed to a certain improvement in their condition before they entered shool. On the other hand, distractibility was observed frequently in all the age groups. In school life, rudeness and distractibility were observed more frequently in the high-age group than in the low-age group. On the other hand, restlessness was less frequent in the high-age group than in the low-age group. ADD-children had a high prevalence, more than 60% , of misbehavior such as temper tantrums, braking rules and criticizing other children excessively in their interpersonal relationships. The number of children with normal abilities of drawing and manual arts was greater in the high-age group than in the low-age group. More than 70% of all the children had attained elementary abilities of reading and writing. But 50-67.5% of the ADD-children had poor school records, and the high-age group received low marks more frequently than the low-age group. A higher prevalence of perinatal disorders was observed among the ADD-children, but there was no relationship between this prevalence and the degree of their maladaptation in daily and school life. Their IQ level was found to have no relation to their school records, and it was demonstrated that the earlier the first consultation was conducted, the more positive was the effect on the children's adaptation.