Mediastinal haemangiomas pose diagnostic and therapeutic challenges owing to their rarity and complex anatomy. A 36-year-old man, with a history of smoking and drinking, presented with a posterior mediastinal mass with back pain. Initial investigations suggested a lymphangioma. However, owing to persistent symptoms and complex pathology, we performed surgical intervention involving open resection of the tumour, which was closely associated with the descending aorta and extended into the right posterior mediastinum. The surgical approach was influenced by the proximity of the tumour to vital structures, necessitating an open procedure. Postoperative complications included chylothorax, managed with a fat-free diet. The final pathological diagnosis was consistent with a benign vascular tumour with a low proliferative rate. Two months post-surgery, computed tomography revealed no complications, and the patient's pain had decreased. A multidisciplinary approach and surgical intervention played important roles in the diagnosis and treatment of this posterior mediastinal haemangioma.Published by Oxford University Press and JSCR Publishing Ltd. © The Author(s) 2024.