Aiming at the characteristics of multi-source panoramic information and highly complex heterogeneous of power Internet of Things devices, this paper proposes a multi-source heterogeneous data aggregation method. Through the data access process of Restful Web service and the quick service bus, the problem of distributed-environment data being difficult to effectively operate is solved with the method, and thus the service process arrangement, management and monitoring can be facilitated. By setting up the heterogeneous source data to RDF data via the RDF interface, and constructing the mapping between the local ontology and the global ontology via combination of the OWL ontology and SWRL rule, the key problem of semantic heterogeneity in the aggregation process can be solved. This method can shield the difference of the physics and logic of the underlying data source, and have good maintainability and expansibility.