In this paper, one type of a security system for panel working is suggested. The industrial Ethernet is used for open-close door control of the working panel and for monitoring the working panel is correct or not. Especially to upgrade the security system, a remote approval function of panel working by using the given approval number, a remote monitoring function for checking the approved panel is currently working or not, and an alarming function for keying the unapproved number or opening the disapproved panel, are added for preventing and reducing the intentional working error. Also the worker and working time are stored in PC automatically in exel file for detecting the working error. To show the possibility of suggested security system. two-working panel system is prepared and studied.