In mindful meditation, negative thoughts such as obsessive thoughts are observed simply as mental events that come and go, rather than as accurate reflections of reality. This experimental study tested the efficacy of a mindfulness-based instruction compared to distraction during brief exposure to obsessive thoughts in obsessive–compulsive patients. Thirty patients diagnosed with obsessive–compulsive disorder were asked to listen to their own obsessive thoughts through headphones during three time phases: at baseline, during an experimental condition and during a return to baseline. During the experimental condition, they were instructed to deal with their obsessive thoughts using either a mindfulness-based strategy or a distraction strategy (random allocation). Results showed that a mindfulness-based strategy reduced anxiety and urge to neutralize from first to second baseline, whereas a distraction strategy did not. Data offer initial evidence that using mindfulness-based metaphors during brief exposure with obsessive thoughts may be a useful alternative to distraction.