To solve the problems of ambiguity，subjective interpretation，and inefficient utilization in the process of reading the text of rail transit design specifications，this paper explores the standardized content construction method of the rail transit design specifications text，proposes a solution based on knowledge graphs. Through structured analysis and ontology modeling of design specifications，taking fire protection review related specifications as research object，a rail transit fire protection review specification knowledge graph is constructed which realizes the application of design requirement query and design statistical analysis based on standardized knowledge structure. Research shows that this method can effectively improve the utilization efficiency of design specifications and provide new technical support for the utilization of rail transit engineering design knowledge.