BackgroundAs the incidence of gastric cancer increases sharply in adults aged over 45 years, a better understanding of gastric cancer screening knowledge and practice is crucial to promote cancer-screening services. This study aimed to evaluate knowledge of early gastric cancer screening, adherence to screening, and perceived barriers hindering screening practices among adults aged ≥ 45 years in China.MethodsA multi-center, face-to-face, cross-sectional study was conducted in community sites in Shijiazhuang, China, through the distribution of structured questionnaires from August to September, 2022.ResultsOf the 1053 respondents, only 13.4% demonstrated a good understanding of early gastric cancer screening. While 64.0% knew that gastroscopy is the gold standard for screening (“how to screen”), only 19.9% were aware of the recommended starting age (“when to screen”). Moreover, less than half could correctly identify high-risk groups (“whom to screen”), with awareness ranging from 20.5% for those infected with H. pylori to 47.8% for those with gastric diseases. Independent factors related to higher screening knowledge included female sex (OR = 1.55, 95% CI = 1.01–2.38), higher education level (OR = 4.03, 95% CI = 2.68–6.06), being with a personal/family experience of gastric diseases (OR = 1.68, 95% CI = 1.12–2.52). In addition, only 23.4% of respondents underwent GC screening. The dominant barrier to early screening was the “absence of symptoms or signs”, followed by “fearing procedural discomfort”.ConclusionThis study highlights significant gaps in early gastric cancer screening knowledge and participation among middle-aged and elderly individuals in China. Addressing these gaps through culturally tailored health education campaigns is a critical strategy for increasing public awareness and participation.