In order to realize rapid discovery and scientific rescue of life after earthquake disaster, multi-source data is needed. Remote sensing data, scene environment data, distribution data of dangerous facilities, life signs data acquired by life detection equipment, status data of life detection equipment, and historical data constitute multi-source heterogeneous data sets in emergency rescue scenarios. Aiming at the application requirements of unified data supervision and multi-dimensional analysis in the field of emergency rescue, this work deeply studies the three-dimensional spatial fusion analysis technology of multi-source heterogeneous data, proposes a plug-in-free three-dimensional spatial fusion scheme based on WebGL rendering technology, and develops a visualization system of emergency rescue data fusion. Fusion and expression of multi-source heterogeneous data needed in emergency rescue scenarios can be realized under the unified space-time framework. It can assist operators to conduct joint dynamic potential analysis, help commanders to make command decisions, and greatly improve the efficiency of emergency rescue field applications.