A plant monitoring control system comprising: a VDU terminal for displaying an operating state and process amount information of a plant as a monitoring control screen; a touch position detecting section for detecting a touch position on a display screen using a touch panel located at a display surface of said display screen of said VDU terminal; and a plant monitoring control unit including: a screen information database in which graphics corresponding to display screen elements, and screen display information of a monitoring control screen to be displayed on said display screen of said VDU terminal have preliminarily been registered; a screen display module for making a drawing processing for displaying the operating state and process amount information of a plant on said display screen of said VDU terminal; and an operation signal generation module for generating an operation signal of the plant using operation information forming part of the screen display information having preliminarily been registered in said screen information database and touch position information to be detected by said touch position detecting section; characterised in that, based on the touch position information detected by said touch position detecting section, the screen display module is adapted to confirm whether or not the touch position information corresponds to a request screen ID forming part of the preliminarily registered screen display information for a currently displayed screen, or if the touch position information corresponds to the operation information, wherein, when the touch position information corresponds to the request screen ID, the screen display module is adapted to erase the currently displayed screen and display an updated display screen on the basis of the preliminarily registered graphics fetched from said screen information database, and process data of the plant that is linked to said display screen read via a network. a VDU terminal for displaying an operating state and process amount information of a plant as a monitoring control screen; a touch position detecting section for detecting a touch position on a display screen using a touch panel located at a display surface of said display screen of said VDU terminal; and a plant monitoring control unit including: a screen information database in which graphics corresponding to display screen elements, and screen display information of a monitoring control screen to be displayed on said display screen of said VDU terminal have preliminarily been registered; a screen display module for making a drawing processing for displaying the operating state and process amount information of a plant on said display screen of said VDU terminal; and an operation signal generation module for generating an operation signal of the plant using operation information forming part of the screen display information having preliminarily been registered in said screen information database and touch position information to be detected by said touch position detecting section; characterised in that, based on the touch position information detected by said touch position detecting section, the screen display module is adapted to confirm whether or not the touch position information corresponds to a request screen ID forming part of the preliminarily registered screen display information for a currently displayed screen, or if the touch position information corresponds to the operation information, wherein, when the touch position information corresponds to the request screen ID, the screen display module is adapted to erase the currently displayed screen and display an updated display screen on the basis of the preliminarily registered graphics fetched from said screen information database, and process data of the plant that is linked to said display screen read via a network. a screen information database in which graphics corresponding to display screen elements, and screen display information of a monitoring control screen to be displayed on said display screen of said VDU terminal have preliminarily been registered; a screen display module for making a drawing processing for displaying the operating state and process amount information of a plant on said display screen of said VDU terminal; and an operation signal generation module for generating an operation signal of the plant using operation information forming part of the screen display information having preliminarily been registered in said screen information database and touch position information to be detected by said touch position detecting section; characterised in that, based on the touch position information detected by said touch position detecting section, the screen display module is adapted to confirm whether or not the touch position information corresponds to a request screen ID forming part of the preliminarily registered screen display information for a currently displayed screen, or if the touch position information corresponds to the operation information, wherein, when the touch position information corresponds to the request screen ID, the screen display module is adapted to erase the currently displayed screen and display an updated display screen on the basis of the preliminarily registered graphics fetched from said screen information database, and process data of the plant that is linked to said display screen read via a network.