The aim of this paper was to test the invariance of Attention Deficit Hyperactivity Disorder (ADHD) symptoms in a sample of 634 children attending to gender. We firstly examined the fit to the data of five models using confirmatory factor analysis, and ordinal logistic regression was used as a method of estimation of both uniform and non-uniform differential item functioning (DIF). The results showed that (a) the three correlated factors model was the best fit model, and (b) there was no gender-specific DIF, either in the ordinal rating form (scale of 1 to 4) or the binary rating form (0-1). These results support that the Diagnostic and Statistical Manual of Mental Disorders DSM-IV-TR does not establish ADHD differential diagnosis criteria for boys and girls.