Although epidermoid cysts are uncommon masses in the testis, their pathogenesis are still under discussion. They must be distinguished from teratomas and dermoid cysts. Especially the distinction from teratomas is much more important because of their malignant potential. Our case represents a patient, aged 31, suffering from a painless mass, measuring 4 cm in its greatest dimension in his left testis. Histologically, a fibrous wall was lined by keratinized squamous epithelium without skin appendages. Considering the pathogenesis, differential diagnosis and treatment, we think that this case is worth of discussion.