Background This study examined the potential feasibility and utility of trigeminal nerve stimulation (TNS) for attention-deficit/hyperactivity disorder (ADHD) in youth. Methods Twenty-four participants ages 7–14 with ADHD enrolled in an 8-week open trial of TNS administered nightly during sleep, and were assessed weekly with parent- and physician-completed measures of ADHD symptoms and executive functioning as well as measures of treatment compliance, adverse events, and side effects. Computerized tests of cognitive functioning were administered at baseline and weeks 4 and 8. Results Significant improvements were seen on the ADHD-IV Rating Scale (P < .0001) and parent-completed Conners Global Index (P < .0001), as well as the majority of scales on the parent-completed Behavior Rating Inventory of Executive Functioning (BRIEF). Improvements were also noted on the computerized Attention Network Task (ANT) Incongruent Reaction Time (P = .006), suggesting that TNS has positive effects on response inhibition. Conclusions TNS therapy for youth with ADHD appears to be both feasible and without significant risk. Subjective improvements on rating scales and laboratory measures of cognition suggest a potential role for TNS in treating ADHD that merits further investigation. Future research in anticipation of designing definitive controlled efficacy trials should evaluate time to onset of TNS response and durability of treatment effects following TNS discontinuation, as well as validate an effective active sham comparator suitable for blinded studies.