Conjunctival edema in surgical patients is known to be a complication resulting from various causative factors. We have observed 30 cases during genral anesthesia in the last 5 months. They were analyzed in terms of distribution of age, sex, blood loss, transfusion and appearence of edema during general anesthesia. 1) Ether is known as an anesthetic to cause it. 2) Position of patient (Trendelenburg position). 3) Mechanical disturbance of venous return such as open heart surgery and neck surgery. 4) Continuous positive pressure ventilation. 5) Reduction of plasma oncotic pressure. (l.V. fluid) 6) Circulatory overloading. 7) Miscellaneous local factors. Therefore, conjunctival edema can be avoided by prevention of the above factors.