Insulated gate bipolar transistor ( IGBT) is a key component of power electronic devices. Its high reliability is an important guarantee for long-term stable operation of the system. Fault monitoring of IGBT modules is one of the effective ways to improve system reliability. Presents a new health-sensitive parameter, gate-emitter pre-on voltage VGE (pre-on) , for monitoring IGBT chip failures in highvoltage multi-chip parallel IGBT modules. First compare existing fault monitoring methods, then build a pre-threshold voltage reliability model, and then detect the IGBT chip failure in the multi-chip high-voltage IGBT module by monitoring VGE (pre-on) during the gate-emitter voltage turn-on transient. In order to verify the feasibility of this method, a 16-chip DIM800NSM33-F IGBT module was simulated. The results show that under different external conditions, the average deviation of the pre-on voltage VGE (pre-on) generated by each parallel IGBT chip failure is about 900 mV, and has high sensitivity and anti-interference ability, which can effectively monitor the IGBT module chip failure.