A 32-year-old male presented with simultaneous bilateral germ cell tumors of the testicles. Histological examination revealed dissimilar histology in both testes showing pure seminoma in the left side and mature teratoma with malignant transformation in the right testicle. A survey of the literature revealed a total of 151 previously described cases of synchronous bilateral germ cell tumors, the majority of which presenting as bilateral seminoma. Treatment of synchronous bilateral germ cell tumors with dissimilar histology should consist of bilateral orchiectomy and bilateral retroperitoneal lymph node dissection.