The present invention relates to a touch screen and a method for positioning a coordinate. The touch screen includes a sensor array layer and a microprocessor. The sensor array layer includes M×N capacitive sensors, wherein M rows of the capacitive sensors are disposed along a first axis, and N columns of the capacitive sensors are disposed along a second axis. The microprocessor includes a plurality of pins correspondingly coupled to the capacitive sensors. When the touch screen is touched to change at least one of sensing values of the capacitive sensors in the sensor array layer, the microprocessor performs an interpolation calculation to determine a touched coordinate according to the sensing values sensed by the capacitive sensors.