Although gastroesophageal reflux disease is a benign disease, it seriously affects the quality of life. Its clinical manifestations are complex and diverse, and the diagnosis requires comprehensive consideration of clinical manifestations and multiple test results, especially for those with atypical symptoms, auxiliary tests are particularly important. The following are the main detection methods: 1. Symptoms and experimental treatment: The main symptoms include acid reflux, heartburn, regurgitation, chest and back pain, which can also cause burning sensation in the throat, foreign body sensation in the throat; nasal congestion, runny nose; breath-holding, wheezing, cough; recurrent oral ulcers, dental caries and so on. Experimental treatment is the use of proton pump inhibitors (such as omeprazole, rabeprazole, esomeprazole) standard dose 2 times/day for 1-2 weeks, and those with significant relief of symptoms can be diagnosed with GERD. However, those who are older, significantly wasted and have difficulty swallowing should be examined and clarified before taking the medication. 2. Endoscopy: Gastroscopy can diagnose reflux esophagitis. Non-erosive reflux disease and Barrett’s esophagus can be further diagnosed by magnifying endoscopy, pigmented endoscopy, fluorescence endoscopy, confocal endoscopy, etc. However, it is not commonly used in clinical practice for technical and economic reasons. 3. Reflux monitoring: 1) Esophageal 24-hour PH monitoring, which has high specificity for monitoring gastroesophageal acid reflux and can monitor whether the symptoms are related to acid reflux. However, the sensitivity is relatively low. (2) Bile reflux monitoring: about half of the patients with GERD have combined duodenal bile reflux in addition to acid reflux, and simultaneous bile reflux monitoring and PH monitoring can improve the positive rate of GERD detection. However, the composition of duodenal fluid is complex and easily influenced by diet and other factors, and bilirubin can change from monomer to heterodimer under acidic conditions, which leads to underestimation of actual reflux, so there are some limitations in clinical application. (3) Intraluminal multichannel impedance monitoring: It is a new monitoring modality that has emerged in recent years, which can monitor a variety of components such as acid, bile and gas in the esophagus, thus dynamically monitoring the movement of gas, liquid and food in the lumen of the esophagus. (4) Esophageal pressure test: abnormal esophageal dynamics in patients with GERD are mainly manifested by reduced lower esophageal sphincter pressure, increased transient relaxation of the lower esophageal sphincter, reduced esophageal contraction frequency, reduced contraction wave amplitude and slowed contraction transmission rate, and increased non-propulsive contractions. The test time is relatively short, and the observed results are mostly non-physiological, with limited sensitivity and specificity. In recent years, methods such as high-resolution manometry and 24-hour manometry have shown their advantages. (5) Upper gastrointestinal tract imaging: the examination can dynamically observe whether there is barium reflux from the stomach into the esophagus. (6) Other: Gastroesophageal reflux detection methods also include acid-induced test, nuclear scan, color ultrasound Doppler examination and marker detection.