Single-site, single-system Langerhans cell histiocytosis (LCH) of the rib is one of the rarest causes of bone tumor in adults. Herein, we report a case of a healthy 35-year-old male who presented with upper back pain that was attributed to a solitary osteolytic lesion at the posterolateral aspect of his sixth rib. For diagnostic confirmation and treatment, partial resection of the sixth rib was performed and pathologic finding was consistent with LCH. At the final follow-up after 2 years, no local recurrence or metastasis was observed.