A two-dimensional model is developed for the heat transfer in a magneto-resistive (MR) head-air bearing system. Using this model, the MR head temperature response is studied for various cases. It is found that the temperature in the head depends on the current through it and the change is only significant within a small area around the MR transducer at the trailing edge. With a typical current value (say 13 mA), the MR head temperature is about 25°C higher than the ambient temperature. When the slider flies over an asperity without contact, the MR temperature fluctuation follows that of the air bearing spacing, which is caused by the cooling effect of the air bearing.