The invention discloses a method and a 
system for constructing and inquiring a 
knowledge graph in the field of science and technology, and belongs to the technical field of science and 
technology management information. According to the method and 
system for constructing and inquiring a 
knowledge graph in the field of science and technology, a user sorts data in a 
relational database, sorts out object, relation and attribute information to be defined, defines the object, relation and attribute information through 
data modeling, and defines mapping information from a 
relational database data table to objects, relations and attributes; and the 
relational database data into is extracted and converted into objects, relations and attribute instances, and the objects, the relations and the attribute instances are stored in a 
graph database, and 
graph query analysis is carried out through attribute value matching. According to the method and 
system for constructing and inquiring a 
knowledge graph in the field of science and technology, the value exploration and 
information discovery requirements of the user on the 
big data gold mine can be better met, and the popularization and application value is very good.