Purpose/Significance To propose data governance and fusion technologies for different business application scenarios for the fusion of multi-source and multi-dimensional big data with complex sources and diverse standards.Method/Process Taking the practice of multi-source and multi-dimensional big data fusion in responding to major public health emergencies as an example, the paper focuses on the challenges faced by multi-source and multi-dimensional big data fusion, the design of the application architecture, technology integration, the implementation path, the application scenarios, etc., and analyzes the application effect and the deficiencies that exist. Result/Conclusion Through the design of intelligent multi-source and multi-dimensional big data fusion technology, real-time monitoring, reading, governance, and interactive correlation of high-frequency updates at 100 billion levels are realized, and intelligent paths are explored for effectively responding to public emergencies.