This study examined parent and child gender effects on parents' attributions and beliefs in regards to child symptoms of attention-deficit/hyperactivity disorder (ADHD). Participants included mothers and fathers of 19 girls and 17 boys with ADHD. Groups of boys and girls, aged 5-13 years, were equated on age and medication status, as well as ADHD symptom severity. These groups also were similar in the severity of comorbid oppositional behaviors and internalizing problems, as well as a variety of demographic characteristics. Parents' attributions for child behavior were assessed in response to written scenarios describing either hyperactive/impulsive or inattentive symptoms of ADHD. Parents also completed a questionnaire assessing beliefs and knowledge about ADHD. There were no child gender effects for parents' attributions or beliefs. All parents attributed inattentive symptoms to more internal, global and stable causes than impulsive symptoms. Mothers attributed both inattentive and impulsive child symptoms to more global and stable causes than did fathers. Fathers, but not mothers, reported more negative reactions to ADHD symptoms that were perceived as having an internal cause. Finally, mothers scored higher on beliefs in behavior management than did fathers, and fathers believed more in psychological causes and treatments for ADHD. Possible explanations for and implications of these results are explored.