Objective To analyze the detection of lesions and influencing factors of opportunistic screening for upper gastrointestinal cancer in Ma'anshan,and to provide the basis for optimizing the early screening strategy. Methods From November 2021 to August 2022,a total of 5 263 permanent residents aged 40-69 years in Ma'anshan were enrolled in the study,and opportunistic screening was conducted by questionnaire surveys,endoscopic examinations and laboratory tests (serum methylation of SFRP2,PG,gastrin 17 and Hp).Multivariate logistic regression was used to analyze the influencing factors of pathological changes. Results The total lesion detection rate was 1.92% (101/5 263),including 0.70% (37/5 263) of upper gastrointestinal cancer and 1.22% (64/5 263) of precancerous lesions.The early diagnosis rate was 63.37% (64/101),and the lesions were mainly located in the stomach (81.19%,82/101).The risk of pathological changes in males was significantly higher than that in females (OR=4.190,95%CI:2.548-6.889).Drinking more than 5 taels (about 250 g) per day was an independent risk factor (OR=2.171,95%CI:1.030-4.575). Conclusion Opportunistic screening can effectively detect early-stage upper gastrointestinal cancer and precancerous lesions,and males and frequent drinkers should be the focus of intervention.It is suggested that screening strategies should be optimized in combination with risk factors.