A tailgut cyst is a congenital cystic lesion that is situated at the presacral and postrectal area and is considered to be a remnant of the tailgut that develops in early fetal life and usually regresses later. Approximately 20 pediatric cases of tailgut cyst have been reported. We report an infantile case of tailgut cyst that was complicated with a skin dimple at the coccygeal region. The cyst was completely resected and the pathological diagnosis was mature teratoma. We finally diagnosed it as a tailgut cyst by several clinical findings including the site of the cyst, MRI image, the fact that it was complicated with a skin dimple, and the pathological findings. 2016 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). A tailgut cyst is a congenital lesion that usually exists at the presacral and postrectal area. It is considered to be a remnant of the tailgut which appears behind the hind gut early in fetal development and usually regresses later . Many adult cases of tailgut cyst have been reported  and some of them showed malignant transformation of the tailgut cyst, which reflected a clinically important aspect [3,4]. Conversely, there are few reports of pediatric tailgut cysts and only approximately 20 cases have been reported [5e14]. We report an infant with a tailgut cyst that was accompanied by a skin dimple at the coccygeal region.