Acute postoperative sialadenitis, called “anesthesia mumps,” has been reported in different surgical procedures. It is usually benign in nature, and the swelling resolves spontaneously without any treatment in the majority of cases. The attending physician should be aware of this transient condition. Very rarely, serious complications can occur such as respiratory distress warranting urgent intervention. We report a case of acute transient sialadenitis in a 6-year-old child who underwent general anesthesia for upper gastrointestinal endoscopy, which resolved spontaneously without any treatment.