Granulosa theca cell tumours represent the largest group of hormone-secreting ovarian tumours and comprise approximately 1.5% of all ovarian malignancy. However, the prognosis and behaviour of pure granulosa cell tumours have been particularly difficult to evaluate, because in previous reports they have been grouped with granulosa theca cell tumours. Consequently, their radiological features and the possible contribution of computed tomography (CT) to clinical management has not been evaluated. We report the CT appearances of 15 patients with pure granulosa cell tumours and their clinical outcome. The results suggest the possibility of a positive relationship between histological grade and FIGO stage at presentation. Large tumour volume, extensive lymph node involvement and ascites on CT are adverse prognostic features. However, patients with abdominal masses less than 9 cm in diameter, absent or small volume lymph node disease and peritoneal and liver metastases achieved complete remission, suggesting that CT can assist in identifying those patients likely to respond best to current therapeutic regimens.