We report on a 28-year-old man presenting with right testicular teratocarcinoma and intratubular germ cell neoplasia (IGCN). Clinically he had a palpable right testicular mass with elevated serum alpha-fetoprotein (AFP). Sonography showed a right testicular mass. Chest x-ray and abdominal computed tomography (CT) revealed no abnormal findings. Under an impression of a clinical stage I testicular tumor, the patient received a right radical orchiectomy. The pathology report showed teratocarcinoma and IGCN. However 3 months later at outpatient follow-up, abdominal CT revealed an enlarged retroperitoneal mass of 2 cm in diameter near the inferior mesenteric artery. Under an impression of metastatic teratocarcinoma, the patient again received modified right retroperitoneal lymph node dissection (RPLND). The pathology report showed metastatic embryonal carcinoma stage pTIIa. The management of testicular teratocarcinoma with IGCN is subsequently discussed