Esophageal cancer has the 8th highest incidence of malignant tumors worldwide, with 412,000 new cases of esophageal cancer worldwide each year. The mortality rate of esophageal cancer is high, with 338,000 deaths of esophageal cancer patients worldwide each year. Esophageal cancer is highly prevalent in the northern part of China. Identifying patients at an early stage is one of the keys to reducing esophageal cancer mortality. Screening helps early detection, diagnosis and treatment of esophageal squamous carcinoma, which is the top priority to prevent esophageal squamous carcinoma and reduce the cumulative mortality of esophageal squamous carcinoma. Combining with the characteristics of high esophageal squamous cancer incidence areas in China, regular screening is recommended for the following groups High risk group of esophageal squamous cancer, those who have any one of the following are considered as high risk group: 1.Long-term living in the area with high incidence of esophageal squamous cancer; 2.First-degree relative with history of esophageal squamous cancer; 3.Past history of esophageal lesion (esophageal intraepithelial neoplasia); 4.Personal history of cancer; 5.Long-term history of smoking; 6.Long-term history of alcohol consumption; 7.Persons with bad eating habits such as eating fast, hot and scalding diet, high salt diet and eating pickles. Gastroscopy is one of the effective means for early diagnosis of esophageal squamous carcinoma and precancerous lesions, and can detect and treat esophageal squamous carcinoma at an early stage.