The agreement between teachers’ and parents’ ratings of the prevalence of DSM-IV attention deficit hyperactivity disorder (ADHD) symptoms and the concordance of the factor structure of ADHD symptoms was analyzed in a sample of 653 Spanish schoolchildren aged 4 to 12 divided into two age groups. The prevalence of ADHD symptoms ranged between 0.66 and 16.73% and was higher when the rater was the teacher. Agreement between parents and teachers was low. Confirmatory factor analysis (CFA) shows a slightly better fit for the three-factor model (Inattention, Hyperactivity and Impulsivity) than for the two-factor model (Inattention and Hyperactivity–impulsivity), except for parents’ ratings in the sample of children under six. CFA using a multitrait–multimethod model (CFA-MTMM) shows similar results.