Hypophyseal adenomas are the most frequent intrasella tumours. They are classified as macroadenomas or as microadenomas depending on whether their size is greater or less than 1 cm. Hypophyseal tumours may undergo ischaemic necrosis and haemorrhage when the blood supply is reduced. Intratumoural bleeding is found in varying percentages, between 9.9% and 26%. We review our series of 122 patients with hypophyseal adenomas in whom MR was done. Signs of bleeding were found in 12 patients (9%). In five cases, bleeding had presented as hypophyseal apoplexy, in five cases with subacute symptoms and in two cases was asymptomatic and diagnosis fortuitous. Of the adenomas with intratumoural bleeding, 9 were functioning tumours (4 secreted PRL, 4 ACTH and 1 GH) and 3 non-functioning. The risk factors considered in the pathogenesis of intratumoural bleeding are numerous. The increased incidence of bleeding in large and in invasisve adenomas, especially when treated with bromocriptin, is well established. MR is the ideal technique to detect intratumoural bleeding, T2 weighted sequences being very useful in the diagnosis of bleeding in the acute phase. In the subacute phase, focal areas of hyperintensity are seen in T1 and of hypo/hyperintensity in T2. In the chronic phase, areas of hypodensity are seen both in T1 and in T2. In our study we analyze the clinico-radiological correlation in patients with signs of intratumoural bleeding.