Abstract INTRODUCTION Malignant paratesticular tumours are rare. We report a case of paratesticular malignant mesothelioma in a patient who had excision of an adenomatoid tumour on the same site in 2 occasions previously. PRESENTATION OF CASE A middle aged man who had an adenomatoid tumour excised from his left hemiscrotum fifteen years previously was referred with a suspicious left epididymal lump. This was followed up sonographically for 2 years until it showed signs of enlargement and testicular invasion; it was then managed with radical orchidectomy. The histology showed paratesticular epithelioid malignant mesothelioma. The patient was referred to the Oncologists for further management. DISCUSSION Paratesticular tumours are commonly benign. Scrotal ultrasonography is the preferred diagnostic imaging method. Paratesticular malignant mesotheliomas are very rare and appear to have poor prognosis. The optimal adjuvant treatment post radical orchidectomy is not established yet. In our case there is suggestion of possible malignant transformation from previous adenomatoid tumour. CONCLUSION In recurrent paratesticular tumours the clinicians should question the possibility of malignant transformation and manage these cases accordingly.