Recent international studies have reported a considerable increase in the diagnosis of attention deficit hyperactivity disorder (ADHD). Data from German statutory health insurance companies suggest a comparable trend for Germany. Based on data from the nationally representative study KiGGS Wave 1 (2009-2012) it was the aim of this study to report on the prevalence rates of parent-reported ADHD diagnoses in children and adolescents aged 3-17 years as well as to report on time trends in comparison with the KiGGS baseline study (2003-2006). ADHD caseness was met if a parent reported that a physician or a psychologist diagnosed their child with ADHD. Participants without a reported ADHD diagnosis but who scored ≥ 7 (clinical range) on the parent-rated hyperactivity subscale of the Strengths and Difficulties Questionnaire (SDQ) were considered as potential ADHD cases. The prevalence of diagnosed ADHD was 5.0% (prevalence of potential ADHD cases 6.0%). An ADHD diagnosis was more than four and a half times more likely to be reported among boys than girls. Children from families with low socioeconomic status (SES) were more than two and a half times more likely to be diagnosed with ADHD than children from families with high SES. Among potential cases, boys were twice as common as girls, and children from families with low SES were approximately three times more common compared with those from high SES families. The proportion of lifetime ADHD diagnoses increased with age and was highest in 11- to 17-year-olds. In every fifth child with ADHD the initial diagnosis was made by the age of 6 years and in 1 out of 11 children with ADHD the initial diagnosis was made by the age of 5 years. In total, we observed no significant changes regarding the frequency of ADHD diagnosis compared to the KiGGS baseline study. Increases reported using data from German statuary health insurance companies were not reflected in the KiGGS data.