Background: Attention-Deficit/Hyperactivity Disorder (ADHD) is a common childhood-onset neuropsychiatric disorder (7.5% in Taiwan) with great impact on individual, family, and society. The diagnosis of ADHD is mainly based on clinical interview of parents and children with assistance of teachers' reports. Self-administered rating scales are useful for screening, assistance of diagnosis, and measurement of symptom changes over time or due to treatment effect. The goals of this study are to establish the norms and psychometric properties of the Chinese version of teacher and parent forms of the Swanson, Nolan, and Pelham, version IV (SNAP-IV) and the teacher, parent, and student forms of the Strengths and Difficulties Questionnaire (SDQ) for future studies on ADHD in Taiwanese populations.