·AIM: To report an unusual presentation of a rapid increase in size of an orbital schwannoma secondary to intratumoural haemorrhage.·METHODS: A case report.·RESULTS: A 79-year-old male patient had a 2 year history of a slow-growing lump over the medial aspect of his left upper eyelid. The lump had further increased in size recently. An incision biopsy was undertaken. However, during the following 4 weeks, the mass rapidly grew in size and had reduced his vision in the left eye to 6/18. He was referred to the orbit service for further management. On examination, he had a large mass emerging from the supero-medial aspect of his orbit. He had mechanical ptosis and the globe was displaced infero-laterally. Eye movements were limited in the left eye, especially in upgaze. A CT scan demonstrated an extraconal mass in the medial aspect of the left orbit. A left anterior orbitotomy with excision biopsy of the mass showed a well encapsulated mass. Histological examination demonstrated a schwannoma with cystic changes and thrombosed blood vessels. The patient had an uneventful postoperative course. Postoperatively his vision improved to 6/6 and he no longer experienced diplopia. ·CONCLUSION: Our case emphasises the point that orbital schwannomas should be regarded as an important differential diagnosis for a slow growing tumour, but the rapid growth, of a previously presumed benign tumour, which can make it highly suspicious for malignancy or inflammation, could also represent intratumoural haemorrhage.