Hysteroscopy is utilized for making the diagnosis and treating a series of uterine disease. It's advantages are more accurate removal of lesion, a short operating time, low morbidity and rapid postoperative recovery. However, serious complications can happen following hysteroscopic surgery. The complications can be divided into the procedure-related, media-related and postoperative events. The procedure-related complications include cervical laceration, uterine perforation, bowel and bladder injury, and hemorrhage. The media-related complications include hyponatremia, gas embolism and excessive fluid absorption. The postoperative events include endometritis and postoperative synechiae. We experienced hyponatermia with pulmonary edema due to excessive fuid absorption in a 52-year-old woman who underwent elective hysteroscopic myomectomy under general anesthesia. She was treated with oxygen therapy, normal saline and furosemide and she recovered without sequelae.