Primary epididymal malignancies are uncommon and usually benign. Benign paratesticular tumors are most commonly adenomatoid, while the most common malignant paratesticular tumors are rhabdomyosarcomas. Approximately 25% of all epididymal tumors are malignant, and of the benign tumors, 60% to 78% are adenomatoid tumors. According to a recent MEDLINE search using epididymis and adenocarcinoma as key words, reports of a primary epididymal adenocarcinoma are extremely rare with only 23 cases in the literature. We report a case of epididymal adenocarcinoma with clinical follow up and metastatic natural history of this rare malignancy.