The present invention provides A control device for determining 4-wire or 5-wire resistive touch screen, comprising: detecting means for respectively sending 4-wire control instruction and 5-wire control instruction in the period before sending control instructions of fetching X-axis and Y-axis coordinate position, so as to detect whether a 4-wire resistive touch screen or 5-wire resistive touch screen are being attached; control means, in accordance with the detected result of the detecting means, the control device is switched to 4-wire or 5-wire resistive touch screen so as to fetch the coordinate position.