We report a case of cauda equine syndrome following caudal anesthesia possibly caused by metastatic spine tumor. Male, 80-year-old, who had prostatic carcinoma with $L_3$ and $L_4$ spine metastasis was scheduled for bilateral orchiectomy. Twenty two-gauge needle was introduced at sacral hiatus and 15 ml of 2% lidocaine administered. The next morning, patient complained of perineal numbness and urination difficulty. During the next several day patient had episodes of fecal incontinence and motor weakness on both lower extremities. This case reminded us that neuroaxial blocks such as spinal, epidural and caudal anesthesia, should be used with extreme care in patients having neoplasm with high incidence of spine metastasis.