Objective:To analyze the application value of health education based on knowledge, attitude and practice (KAP) in patients before gastrointestinal endoscopy in the Department of Gastroenterology.Methods:Three hundred and fifty patients underwent gastrointestinal endoscopy in the Department of Gastroenterology of Jingqiao Health Center of Nanjing Lishui District from January 2019 to October 2020 were selected and divided into the control group ( n=175) and the observation group ( n=175) according to the random number table method. Patients in the control group chose regular health education, and patients in the observation group adopted health education in the KAP model. The gastrointestinal cleanliness before the examination, the Self-rating Anxiety Scale (SAS) score before and after the examination, the awareness rate of medical knowledge, the examination compliance rate, the diet compliance rate and the nursing satisfaction rate were compared between the two groups of patients. Results:Patients of gastrointestinal cleanliness level 1, 2, 3, and 4 in the observation group accounted for 83.43% (146/175), 13.14% (23/175), 3.43% (6/175) and 0, respectively, and those in the control group were 49.71% (87/175), 35.43% (62/175), 9.14% (17/175) and 4.57% (8/175) ( Z value was 6.743, P<0.001). The SAS scores of the observation group after the examination was 42.30±4.77, and 50.17±5.12 in the control group. There was significant difference between the two groups after the examination ( t value was 14.878, P<0.05). The medical-related knowledge awareness rate, the inspection compliance rate, and the diet compliance rate of the observation group were 100.00%(175/175), 98.29% (172/175) and 97.71%(171/175), and those rates of the control group were 90.29%(158/175), 83.43% (146/175), and 79.43%(139/175), respectively ( χ2 value was 17.867, 23.250, 28.903, all P<0.05). Conclusions:The knowledge-attitude-practice model-based health education can reduce the preoperative anxiety of patients undergoing gastrointestinal endoscopy, and improve their compliance and satisfaction with nursing.