Background: Control over the tendency to make or withhold responses based on contextual Pavlovian information, might play a key role in understanding impulsivity/hyperactivity in ADHD. Here we set out to assess (1) the understudied relation between Pavlovian inhibitory control and hyperactivity/impulsivity in adults with ADHD and (2) whether this inhibition can be enhanced by mindfulness based cognitive therapy (MBCT).Methods: 50 Adult ADHD patients were assessed before and after 8 weeks of treatment as usual (TAU) with (n=24) or without (n=26) MBCT. We employed a sophisticated, well-established Pavlovian-to-instrumental transfer task that quantifies Pavlovian control over instrumental behavior. Results: Task results revealed (1) less aversive Pavlovian inhibition in patients with clinical hyperactivity/impulsivity; and (2) enhanced inhibition after TAU+MBCT compared with TAU. Conclusions: Aversive Pavlovian inhibition plays a role in clinically relevant hyperactivity/impulsivity in adult ADHD and MBCT can be used to enhance this form of inhibition.