Recurrence of teratoma or carcinoma in testis cancer patients found to have teratoma at post-chemotherapy retroperitoneal lymphadenectomy is well recognized. We report a case of an intra-abdominal desmoid tumor discovered 2 years following post-chemotherapy retroperitoneal lymphadenectomy in a testis cancer patient who had teratoma at the time of lymphadenectomy. To our knowledge this is the first case of an intra-abdominal desmoid tumor discovered in this setting. The characteristics and treatment considerations of this unusual tumor are described. Desmoid tumor should be included in the differential diagnosis of tumor recurrence in testis cancer patients previously subjected to post-chemotherapy retroperitoneal lymphadenectomy.