Abstract: In the context of severe challenges posed by the frequent emerging infectious diseases and increased antimicrobial resistance, the "One Health" strategy, which integrates human, animal, and environmental health, facilitates public health from passive response to active surveillance. As a critical medium among humans, animals, and environment, wastewater can provide the information about pathogens and antimicrobial resistance genes (ARGs) from both humans and animal. Wastewater-based epidemiology (WBE) meets the requirement for active surveillance at human-animal-environment level, which has the advantages of non-invasiveness, cost-effectiveness, and timely assessment of regional health status and can be used to address the limitations of traditional clinical surveillance in identifying asymptomatic infections and providing early warnings. This paper systematically summarizes the technical workflow of WBE, including sample collection, pathogen concentration, molecular detection, and data analysis, introduces the applications of WBE in zoonotic disease surveillance, outbreak source tracking, and assessment of the spread of ARGs and discuss the key pathways for integrating multi-source health data to transform WBE from a single surveillance tool to a systematic platform supporting public health decision-making to provide technical insights for the implementation of One Health .