In the KEKB magnet control system, relational database management system (RDBMS) has been used for the management of the device configuration. Most of the device parameters, such as address of the interfaces, constant parameters of the magnet power supplies, excitation functions of the magnets, limit values for the operation, etc. are stored in the RDBMS. These parameters are used mainly for the macro expansion to generate the runtime EPICS database files. They are also used to configure the high level application programs. Although this scheme is flexible, it is heavy to maintain with little man power in the KEKB control group. To reduce the maintenance cost, restructuring of this scheme is planned. The plan consists of two major changes. One is the reducing data and making data structure simpler. Another is the replacing tools with simpler ones. As the part of the restructuring, the replacement of the RDBMS with a simple configuration files is planned. The configuration file has simple text format, which is designed easy to read and easy to modify only using text editor. The detailed design of the format and its application to the KEKB magnet control system are presented.