The objective of this research is to non-invasively sense switching power semiconductor junction temperature (Tj) in real time. By applying simple circuitry to the gate drive output current, a non-invasive, high bandwidth, and real-time switching power semiconductor Tj sensing can be achieved without an additional temperature sensor. The methodology used to sense a switching power semiconductor Tj is based on the Tj dependency of the “gate drive – switching power semiconductor” interactions during the switching transient. Depending on the type and fabrication of the switching power semiconductor, the gate drive output transient current properties such as peak value, time constant, Miller Plateau duration, and so forth are affected by Tj. Analog signal processing is applied to the gate drive turn-on output current transient in real-time, and the processed current signal is correlated to Tj. The “processed current – Tj” relationship is used for real-time Tj sensing. The online estimated switching power semiconductor Tj is calibrated by testing an un-encapsulated device with a thermal camera. In this research, all sensing hardware are implemented on the gate drive side; not in the power device or on the power circuit side. Real-time Tj estimation is achieved in each switching cycle, and this will potentially benefit switching power semiconductor active ΔTj control. The methodology is verified on most of the mainstream switching power semiconductors (IGBT, SiC MOSFET, etc.), different types of gate drive topologies, and a wide range of power levels.