A method and a structure for measuring the temperature of heating elements of an ink-jet printhead are provided, wherein an extra metal layer or semiconductor layer is formed on the ink-jet chip having driving elements to precisely measure the temperature of each individual heating element. The structure includes: an ink-jet device including a heating element for heating liquid ink; a transistor driver for driving a transistor to control heating of the heating element; and a temperature-sensing layer located between the ink-jet device and the transistor driver and under the heating element, the temperature-sensing layer having two terminals, one connecting to the transistor and the other connecting to an electrode terminal connected to a printer, wherein the ink-jet device connects to the transistor driver through the temperature-sensing layer.