Based on dysexecutive function theory of Attention deficit-hyperactivity disorder (ADHD), inhibitory control plays a crucial role in ADHD symptoms and respective behavioral problems. In the present study, 30 preschoolers with ADHD were recruited in a random clinical trial design in two control and intervention groups. The Flanker and Go/No-Go tasks, Swanson, Nolan, and Pelham Rating Scale, and Child Behavior Checklist were used for assessment at baseline, after the intervention, and 1-month follow-up sessions. The program for attentive rehabilitation of inhibition and selective attention (PARISA) was used for intervention in 10-12 sessions. Findings showed an improvement in prepotent inhibition and interference control in the intervention group. Furthermore, the hyperactivity/impulsivity symptoms were ameliorated, and the externalizing behavioral problems were improved after the intervention. Inhibitory control in preschoolers with ADHD is trainable, and the training gain could be transferred to ADHD symptoms and externalizing behavior.