Background: Not all patients suffering from trichotillomania (TTM) recover completely using CBT and of those that do, only a few maintain their recovery over time. Aims: The purpose of the present study was to investigate the effectiveness of metacognitive methods combined with habit reversal (MCT/HRT) in trichotillomania with a relatively long-term follow-up. Method: A case series (n = 8) and a randomized wait-list controlled trial (n = 34) design were conducted in this study. In the case series, three of the eight patients dropped out of the study. Therefore, TTM-related symptoms were evaluated in five patients suffering from TTM before and after brief metacognitive plus habit reversal therapy during 1-month, 6-month, and 12-month follow-ups. The treatment consisted of detached mindfulness (DM) techniques, ritual postponement and habit reversal training (HRT) in eight sessions. Results: All patients were responders at post-treatment in case series. After the 12-month follow-up, the results were associated with higher pre-treatment levels of self-esteem and global functioning and lower pre-treatment levels of depression and anxiety with nearly complete abstinence from hair pulling immediately after treatment. A randomized wait-list controlled trial with experimental (n = 17) and waiting list group (n = 17) was then conducted to confirm the case series results. There were significant differences between the two groups regarding changes in MGH-HPS, Y-BOCS-TM, RSES, GAF, BDI, BAI and self-monitoring. Therefore, the MCT/HRT treatment was found to be more effective than the waiting list group. Conclusions: A combined treatment including metacognitive and habit reversal techniques is remarkably effective in patients with TTM.