PURPOSE: To process data in parallel to improve the processing capability by independently converting data for IC card in each data conversion processing part and transferring converted data to an issue processing part through a host computer to perform the processing.

CONSTITUTION: Plural data conversion processing parts and the issue processing part are connected to one host computer by a communication line 12 to constitute a network. Each data conversion processing part 13 consists of a data converter 13b and a personal computer 13a, and the data converter 13b generates a data file for IC card, and it is read in by the personal computer 13a. Read data is written in a memory and is transferred to the host computer 10 through the communication line 12. The host computer 10 sums up transferred data and stores it in a memory 11. The IC data file written in the memory 11 is transferred to a personal computer 15a of the assigned issue processing part. Flies coinciding with collation information are retrieved to successively issue IC cards.