Aiming at the problem that using multi-source heterogeneous environmental data is difficult, based on the general knowledge graph, this study constructed the environmental knowledge graph by fusing various environmental data. Firstly, the environmental data are obtained by using Web crawlers and preprocessed later; then, data conversion, text extraction, and data fusion technologies are used to build the knowledge graph; finally, the generated knowledge graph is stored in the graph database, and then we build a knowledge graph application platform to provide a way to searching information recursively and to realize the visualization environmental knowledge graph. Such platform is more comprehensive thus it may offer better references for the relative personnel.