Epidermoid cysts of the testes are rare, benign lesions that account for approximately 1% of all testicular tumors. They present most often between the second and fourth decade of life, and have been reported in prepubertal children rarely. The authors report the clinical and sonographic findings in a 4 1/2-year-old child with a testicular epidermoid cyst, and they analyze the 22 prepubertal cases found in the world literature. As described below, the clinical and sonographic features of this tumor are not specific for an epidermoid cyst and do not preclude a teratomatous or malignant neoplasm. This case adds to the varied sonographic appearance of prepubertal testicular epidermoid cysts. The lack of either unique clinical or sonographic features would suggest that extreme caution be used if local excision is considered for a patient with presumed epidermoid cyst of the testicle.