To improve the security of a system by registering/collating an operation command permitted only by a menu operation to/with a table.

A menu command file is read based on a menu command file indicated from a system manager. Various commands are registered in the menu command file 80 and the command which requires the authority of the system manager is extracted among them and the result is written into an access authority table 50. A command name, system operator user ID and a command parameter are stored in the access authority table 50 as one entry. A menu processing program successively reads the commands on the menu command file 80 and executes the commands as they are with system operator authority as they are when the commands registered in the access authority management table 50 are not matched with user 10.