Malignant mesothelioma occurs commonly in the peritonial cavity, pleural and pericardial cavity, also have been reconginzed in numerous other locations. However, it is rarely found in testis arised from tunica vaginalis. Aggressive surgery is necessary soon after diagnosis. Generally the prognosis is very poor and there is no consensus regarding treatment after surgery. We report a case of a 44 years old man with scrotal mass with recurrent pain for 2 years and pathologically diagnosed as a malignant mesothelioma in tunica vaginalis.