Pyogenic granuloma (PG) is a benign acquired vascular tumor that frequently involves nail apparatus. The periungual PG can appear after local traumas including self-induced nail injuries, in which the clinical history is essential in its diagnosis. Although diverse treatment modalities could be counted, treating periungual PG is challenging due to high vascularity of the nail unit and possibility of the nail dystrophy. We herein report an interesting case of periungual PG successfully treated with carbon dioxide laser. A 51-year-old female was referred to our dermatologic clinic for an erythematous nodule with an eroded surface and crusts at the right thumbnail. The lesion occurred when she was peeling off the stickers with her fingertips 10 days ago. She was affected by onychotillomania, and demonstrated an apparent lack of cuticle due to the frequent picking at the proximal nail fold. This might have damaged the adjacent ventral nail matrix, causing the washboard deformity and contributing to partial defect of the nail plate. After using antibiotics and stopping her nail manipulation for a week, the size of the lesion had been partially reduced. Then, the rest was removed with a single session of the carbon dioxide laser therapy. The PG had not recurred during the follow-up period.