To provide an electronic form data conversion system, a server and the like that can transmit/receive data using an electronic form between a client and the database of the server that are connected through a network or the like.

If information on the transmission/reception of the electronic form, information on the association between the electronic form and the data, and the like that are inputted in an active check sheet 110 are transmitted, the server 104 creates a mapping definition file based on the transmitted information. The server 104 extracts the electronic form and the data selected by the client 102 from an electronic form library management part 108 and a database management part 106, respectively, and disposes the extracted data at the XML tag position of XML data of the electronic form based on the mapping definition file, so that the electronic form and the extracted data are coupled and are displayed for the client 102.