OBJECTIVES: To determine the cost of treatment (CoT) associated with Hyperkinetic Disorder (HD) in Germany by age and sex and compare it to the CoT of other childhood disorders. METHODS: Data on the CoT of various childhood disorders (including HD, epilepsy and asthma) were provided by the German Federal Statistical Office for the year 2002. The data had been gathered by the Federal Office from health insurance providers. The data were broken down by diagnosis, age, sex, and the type of resource consumed (inpatient treatment, outpatient treatment, medication). The CoT of HD was then compared to the CoT of epilepsy and asthma. RESULTS: Total treatment costs of HD were €142 million. The highest costs (€128.8 million) were in the age group 0-15 years, where HD is most prevalent, with 0.93% of insured girls and 3.35% of insured boys affected. Costs also reflect this gender difference in prevalence, with €104.6 million incurred by boys and €24.2 million incurred by girls in this age group. Treatment costs can be primarily attributed to inpatient treatment (41.6%), outpatient treatment (38.9%) and medication (5.7%). The treatment cost of HD represents 2.2% of the total CoT in the age group 0-15 years, estimated to be €5,735 million. In this age group, other disorders such as epilepsy (or asthma) incur treatment costs of €199 million (€245 million). For epilepsy (or asthma), inpatient treatment accounts for 56.1% (18.6%), outpatient treatment for 11.1% (11.1%) and medication for 26.9% (59.0%) of CoT. CONCLUSIONS: In Germany in 2002, the CoT of HD was €128.8 million in the age group 0-15 years. The cost of HD was lower than the cost of other common childhood diseases and represents only 2.2% of the total CoT in the age group 0-15 years. Whilst inpatient treatment for HD incurs 41.6% of CoT, medication incurs 5.7%.