The central antihypertensive agent clonidine is an ${alpha}_2$-adrenergic agonist that possesses pain-relieving properties. It has been administered epidurally in the treatment of cancer pain and for postoperative analgesia. 1) Case 1, 62-year-old woman who suffered from neurogenic pain syndrome due to metastatic squamous cell carcinoma of spinal canal was treated. 2) Case 2, 51-year-old woman undergoing lower abdominal surgery, epidurally administered morphine did not produced postoperative analgesia. In these cases, continuous epidural administeration of clonidine (200ug/day) and 0.3% bupivacaine(12 ml/day) produce high quality pain relief. These results suggest that antinociceptive effect of epidural clonidine is assumed to result from activation of ${alpha}_2$-adrenergic receptors in the dorsal horn of the spinal cord.