Teachers and school counsellors play a key role in the detection of symptoms associated with attention-deficit/hyperactivity disorder (ADHD) and in interventions. The present study aimed to analyse differences in knowledge about and attitudes towards ADHD between five different types of educator: infant education teachers, primary education teachers, special education teachers, school counsellors, and secondary education teachers. The participants were 206 professionals from state-funded and independent schools in the north of Spain who completed the Questionnaire for the Evaluation of Teachers' Knowledge of ADHD (which included four dimensions: general information, symptoms, aetiology and treatment) and the ADHD-Specific Knowledge and Attitudes of Teachers questionnaire (to assess attitudes towards ADHD). Results of univariate analysis of variance showed statistically significant differences between the five different types of educator. School counsellors and special education teachers exhibited greater knowledge and better attitudes towards ADHD. Training programs for teachers in infant, primary and secondary education, should be provided to improve knowledge and attitudes in relation to ADHD.