BACKGROUND: Ablative carbon dioxide fractional laser systems (CO(2) FS) have been effectively used to improve the appearance of scarring after surgical procedures, but an optimal treatment time has not been established. OBJECTIVE: To evaluate the efficacy and safety of CO(2) FS in early postoperative thyroidectomy scars. METHODS: Twenty-three Korean women with thyroidectomy scars were enrolled in this study. All patients underwent a single session of two passes of a CO(2) FS with a pulse energy setting of 50 mJ and a density of 100 spots/cm(2) 2 to 3 weeks after surgery. RESULTS: Mean Vancouver Scar Scale (VSS) scores were statistically significantly lower after laser treatment. Three months after CO(2) FS treatment of thyroidectomy scarring, 12 of 23 participants showed clinical improvement of more than 51% from 2 to 3 weeks after surgery. The mean grade of clinical improvement based on independent clinical assessment was 2.6 ± 0.9. CONCLUSION: Early postoperative CO(2) FS treatment of thyroidectomy scars is effective and safe.