Malignant tumors associated with hernial sacs are rare entities. A review of literature offers only small groups of patients. The high incidence of inguinal hernia repair operations demands recognition of this morbidity. It should be suspected in cases of tight tissue in the hernial sac in differentiation to the unreduced inguinal and femoral hernia. Therapy of choice must be a resection in toto (R0), incomplete resection causes inguinal spreading or recurrence of the tumor. The exact evaluation of the surroundings should follow. There is no other standardized therapy besides operation. A case of leiomyosarcoma in inguinal hernia will present the entity of neoplastic disease in hernial sac.