Objective:To evaluate the application effect of non opioid anesthesia using ketamine in endoscopic submucosal dissection under general anesthesia of gastroscopy and laryngeal mask.Methods:Sixty patients who underwent elective endoscopic submucosal dissection under general anesthesia gastroscopy and laryngeal mask at Nanjing Medical University Affiliated Nanjing Hospital from January to December 2022 were randomly divided into a conventional anesthesia group and a non opioid anesthesia group using a random number table method, with 30 cases in each group. The conventional anesthesia group used opioid drugs, while the non opioid anesthesia group used ketamine instead of opioid drugs. We recorded the incidence of postoperative nausea and vomiting in two groups of patients; Recorded the mean arterial pressure (MAP) and heart rate (HR) of two groups of patients before anesthesia (T 0), during intubation (T 1), at the start of surgery (T 2), and after surgery (T 3); We also recorded the lowest pulse oxygen saturation (SpO 2) after extubation in two groups of patients; At the same time, the surgical time, propofol dosage, extubation time, monitoring time in the anesthesia and resuscitation unit (PACU), incidence of postoperative nausea and vomiting, patient satisfaction, and other adverse reactions were recorded. Results:The difference in surgical time, MAP and HR from T 0 to T 3, and the lowest SpO 2 after extubation between the conventional anesthesia group and the non opioid anesthesia group was not statistically significant (all P>0.05); Compared with the conventional anesthesia group, the non opioid anesthesia group had a lower incidence of postoperative nausea and vomiting, lower dosage of propofol, shorter extubation time and PACU monitoring time, and higher patient satisfaction (all P<0.05); Both groups of patients had no serious adverse reactions. Conclusions:The application of ketamine in endoscopic submucosal dissection during non opioid anesthesia of gastroscopy laryngeal mask has certain advantages over conventional use of opioid drugs, including fast postoperative recovery, low incidence of nausea and vomiting, and high patient satisfaction.