【Abstract】Objective To investigate the clinical characteristics, Helicobacter pylori (H.pylori) infection and risk factors of bile reflux gastritis in plateau area.Methods 243 patients with bile reflux gastritis from July 2018 to September 2019 in Xigaze Branch of The Second Affiliated Hospital of Army Medical University were selected as bile reflux gastritis group, and 243 volunteers without bile reflux gastritis in gastroscopy were selected as control group according to 1〖DK〗∶1. After admission, the two groups were tested for HP, and clinical data were collected, including gender, age, body mass index (BMI), altitude of residence, time of entering Tibet, nationality, family history, military, smoking, drinking, spicy diet, HP infection, and percutaneous oxygen saturation (SPO  2). The clinical characteristics of the two groups were collected and statistically analyzed. The differences of basic information between the two groups were compared. The difference information between the two groups was included in the logistic model, and the quantitative assignment was performed. The occurrence of bile reflux gastritis was taken as the dependent variable (y, yes=1, no=0), and the altitude of residence, time of entering Tibet, nationality, military, smoking, drinking, spicy diet and HP feeling were taken as the independent variables. The risk factors of bile reflux gastritis at high altitude were analyzed.Results The clinical features of bile reflux gastritis in the plateau region are mostly upper abdominal fullness, bitter morning mouth and acid reflux, accounting for 3375%, 2222% and 1523%, respectively. There were no significant differences in gender, age, BMI and family history between the two groups (P＞005). The proportion of patients in the bile reflux gastritis group with residence altitude of ＞3820m, entry time of ＞10 years, Tibetan, military, smoking, drinking, spicy diet, H.pylori infection and SpO2＜80% was significantly higher than that in the control group (P＜005). Logistic analysis confirmed that the risk factors of bile reflux gastritis in the plateau area were ＞3820m at altitude, ＞at entry time for 10 years, Tibetan, military, smoking, drinking, spicy diet, H. pylori infection and SpO2＜80%, all with P＜005. Conclusion Altitude of residence, time of entering Tibet, nationality, soldiers stationed in plateau, smoking, 〖JP2〗drinking, spicy diet, HP infection and low Spo  2 are closely related to the occurrence of bile reflux gastritis in plateau area.