The present study investigated whether the Childhood Executive Function Inventory (CHEXI) can discriminate between young children fulfilling the diagnostic criteria for attention-deficit/hyperactivity disorder (ADHD) and normally developing children. Unlike other executive function rating instruments, the CHEXI focuses specifically on inhibitory control and working memory, without including items that overlap with the diagnostic criteria of ADHD. The CHEXI was found to discriminate very well between children fulfilling the criteria for ADHD and normally developing children, also when controlling for the effect of IQ and socioeconomic status (SES). Both sensitivity and specificity of the two CHEXI subscales were shown to be high using either parent or teacher ratings. The highest overall classification rate was found for parent ratings on the inhibition subscale, with sensitivity and specificity reaching 93.3. To summarize, the CHEXI should be considered a promising measure for identifying young children with ADHD, although it is for future research to determine whether the CHEXI can be successfully used to also discriminate between different psychopathological groups.