(Disclaimer: This article is for general science purposes only. To protect patient privacy, relevant information in the following content has been processed.) Abstract: Diffuse peritonitis has an acute onset. If diffuse peritonitis is present, it indicates a serious condition, which, if not treated promptly, may lead to infectious shock and endanger life. The patient in this case came to the hospital with sudden onset of severe pain throughout the abdomen for 6 hours, and was admitted with diffuse peritonitis after an emergency CT examination of the abdomen. After admission, laparoscopic surgery was performed. Intraoperative diagnosis of diffuse peritonitis and gastric perforation was made, and laparoscopic gastric perforation repair was performed. The patient’s symptoms disappeared after surgery and he recovered well. The patient recovered well. [Basic information] Male, 54 years old [Disease type] Diffuse peritonitis, gastric perforation [Hospital] Jinzhou Central Hospital [Consultation date] June 27, 2021 [Treatment plan] Surgical treatment (laparoscopic exploration, laparoscopic gastric perforation repair) + flushing and drainage of the abdominal cavity + medication (postoperative intravenous piperacillin combined with ornidazole anti-inflammatory, oral omeprazole combined with amoxicillin and clindamycin) [Treatment cycle]. The patient came to the clinic with sudden onset of severe pain in the whole abdomen for 6 hours, and was pushed into the ward by a flat cart with a painful expression. The patient had previous symptoms of pain and discomfort in the stomach, and the pain was aggravated after meals, and the symptoms could be relieved after a certain period of digestion. The abdominal examination showed flat abdomen, no gastrointestinal type and peristaltic wave, whole abdomen with pressure pain and rebound pain, muscle tension in plate-like abdomen, and more obvious pressure pain under the abdominal saber, and the preliminary diagnosis was diffuse peritonitis and upper gastrointestinal perforation. After the patient was hospitalized, the patient first underwent urgent preoperative routine examination, including routine blood count, coagulation function, blood type, biochemistry and other related tests, and explained to the patient that the condition was aggravated, the diagnosis of diffuse peritonitis was clear, and the possibility of upper gastrointestinal perforation was considered, so emergency surgery was recommended. The patient was then operated laparoscopically under emergency general anesthesia, and was seen to have large omentum wrapped around the anterior wall of the stomach at the lesser curvature, yellow pus moss and exudate scattered around the stomach and liver, exudate visible in the pelvis, and a perforation of about 0.5 cm in size on the lesser curvature of the stomach, and was diagnosed with diffuse peritonitis and gastric perforation, and was operated laparoscopically to repair the gastric perforation and flush and drain the abdominal cavity. After the operation, the patient was returned to the ward with intravenous piperacillin combined with ornidazole for anti-inflammatory and other symptomatic treatment. After surgery, the perforated area was repaired, and the septic exudate in the abdominal cavity was attracted and drained by flushing to further relieve the cause of the disease and actively control the symptoms of intra-abdominal infection, and the patient recovered well after surgery, and the abdominal pain was significantly relieved and gradually disappeared. On the second day after the operation, the routine blood test showed that the leukocyte value was significantly lower than before, and other values were also improving significantly. On the seventh day after the operation, the patient resumed eating, and there was no abdominal pain and other discomfort after eating. And because laparoscopic surgery causes little damage to the patient, postoperative recovery is also faster, and the chance of complications such as incisional infection is low. After surgery, the patient was discharged with anti-inflammatory treatment with piperacillin combined with ornidazole, and the white blood cells and neutrophils in the routine blood count decreased to normal. We are very glad that the patient recovered well after surgery and was discharged successfully. After discharge, the patient should pay more attention to rest, and the diet should be gradually changed to a normal diet. Gastroscopy should be completed 3 months after surgery to further clarify the cause of perforation and monitor the healing of gastric perforation. Some light exercises can be done according to the recovery condition to promote recovery and further improve the body immunity. If there is any change in the condition during the recovery period, you can follow up with the general surgery clinic. V. Personal insight Diffuse peritonitis belongs to the acute abdominal disease of general surgery, the onset is generally urgent and requires timely treatment, such as untimely treatment, intra-abdominal infection symptoms are serious, is life-threatening. For many common diseases of the abdomen, symptoms of diffuse peritonitis may occur, such as acute appendicitis, acute pancreatitis, perforation of the digestive tract and other diseases. Therefore, if symptoms of abdominal pain appear, you should go to the hospital as early as possible to avoid delayed treatment and aggravation of the disease and miss the best time for treatment. Generally, through active and symptomatic treatment, the postoperative recovery is good, but it is important to follow the medical advice to take medication on time and to review regularly.