The present invention relates to a conversion system and method for civil engineering model data of a thermal power plant. The conversion system has three sequentially-connected units: a civil engineering structure modeling client cluster, a server cluster and a data acquisition terminal. The civil engineering structure modeling client cluster comprises: a Midas model module, a PDMS module and a material information model that collects statistics of a model engineering quantity. The server cluster comprises: a database server, a data conversion server, a structure computing server and an information query server. The data acquisition terminal comprises: a code printing terminal and an acquisition labeling terminal. The system provided by the present invention connects multiple links in the civil engineering structure, such as the PDMS three-dimensional model, the Midas computing analysis model, the structure auxiliary analysis and computation, and operation and maintenance inspection, effectively integrates isolated data in each link, eliminates the data barrier, greatly improves efficiency and quality of civil engineering in the design stage, reduces data errors caused by human, and also provides a direct data source for the link of operation and maintenance.