ABSTRACT Background The Helicobacter pylori epidemic in China accounts for up to a third of gastric cancers worldwide. We aim to monitor the temporal and spatial dynamics of H . pylori infection in both adults and children across China. Materials and Methods We developed a surveillance system consisting of a data collection component that harnessed survey reports in natural populations and an analysis component that accounted for the differences in survey time and location, population age structure, and H . pylori detection method. System outputs were estimates of the prevalence of H . pylori in adults and children (aged ≤ 14 years) presented at three hierarchical levels (regional, provincial, and prefectural). Results The overall prevalence of H . pylori infection declined sharply in adults (63.3%, 52.5%, 43.4%, and 38.7%) and less sharply in children (23.1%, 26.1%, 16.0%, and 15.7%) in 1983–1999, 2000–2009, 2010–2014, and 2015–2019, respectively. The changes were asynchronous across regions, with the most marked declines in the Northwest, the Hong Kong‐Macao‐Taiwan region, and the East. We estimated that 457.6 million adults and 44.5 million children have been infected with H . pylori , with cross‐province disparities in prevalence ranging from 24.3% to 69.3% among adults and 2.9% to 46.3% among children. In general, the risk level of gastric cancer increased as the prevalence of H . pylori increased. The correlation was statistically significant for both adult men (Spearman coefficient of correlation: 0.393, p = 0.0146) and women (0.470, p = 0.0029). Conclusions The tracking system would be important for the continuous and stratified tracking of the Helicobacter pylori epidemic across China and can be used to furnish an evidence base for the formulation of tailored prevention strategies.