We have shown before that attention deficit hyperactivity disorder (ADHD) children suffer from deficits of sustained attention, while divided, selective and distributed attention is largely spared. The present study explores whether these deficits can be ameliorated by unconscious priming of attention. Sixty children diagnosed with ADHD participated, their age ranged between eight and twelve years. Participants were primed with the scrambled sentence task: under the pretext of a language comprehension task, they were exposed to words referring to focused attention (group “focused”) or scattered attention (group “scattered”), or were not exposed to attention-related words (group “control”). All three groups were then assessed with the same battery of attention tests used in our earlier study. We found that compared to the “control” group, performance was higher in the “focused” group on tests of sustained, divided and distributed attention, and was lower in the “scattered” group on all four tests. From this we conclude that unconscious priming can modify the attention of ADHD children, and that this modification extends to the one attention component that is most affected by ADHD. Unconscious priming might therefore be an expedient supplementary method for ADHD treatment, as it can be administered at virtually no cost anytime, anywhere.