A data item name constituting a source data schema is extracted (1051), a data item name constituting a target data schema is extracted (1052), element concepts included in the extracted data item names of the source data schema and the target data schema are extracted (1053), a distinctive relation between the data item names is set based on the extracted element concepts to be stored in an ontology (1061), the data item names of the source data schema and the target data schema are read, a correlation is set between the two read data item names based on the distinctive relation to be stored in a mapping definition file (1071).