Abstract. TGMR reader is current technology of magnetic recording read sensor which dramatically improves readout amplitude, speed and recording areal density. In advanced manufacturing environment, automated tools are increasingly used and wireless communication device is aimed to be employed to enhance the operation efficiency. However, electromagnetic fields from wireless communication devices could harm or damage the most energy sensitive devices/equipment, such as TGMR reader sensor, in head gimbal assembly process. This study surveys, therefore, electromagnetic interference from wireless communication devices using CTM048, EM Field Meter with CTS001 directional antenna and electromagnetic field module, then use Agilent 34410A to measure TGMR resistance and thermal change of TGMR head while placing in the field of wireless communication device. Build-in Differential-Ended Temperature Coefficient of Resistivity sensor is utilized for proximal TGMR temperature. Impact to electrical performance of TGMR pre and post actions simulating HGA assembly process will be confirmed using Quasi-static Tester..