Peritoneal carcinomatosis from germ-cell tumor has rarely been described, and thus remains largely unknown. We report here five cases involving this entity. All five patients had embryonal carcinoma in their primary germ-cell tumor. Four of them had undergone retroperitoneal lymph node dissection (RPLND), and viable malignant cells were found. RPLND was performed for relapses (n = 3) and as primary therapy for stage II disease (n = 1). The peritoneum was the only site of relapse in three patients, and was associated with pleural effusion in one. The time to relapse after RPLND ranged from 6 to 14 months. One patient sustained injury to lymph nodes during RPLND, and another patient had a peritoneal xanthelasma. The only three patients already described in the literature underwent RPLND or surgical biopsy. All these observations suggest a striking relation between RPLND and occurrence of subsequent peritoneal carcinomatosis.