In order to accurately estimate junction temperature, the temperature characteristics of insulated gate bipolar transistors (IGBTs) and junction temperature estimation method based on temperature sensitive electrical parameters (TSEP) are studied in this paper. The gate-emitter voltage Vge, collector-emitter voltage Vce, and collector current Ic in different case temperature are measured during switching process, which are used as TSEP. The paper first analyzes the mechanism that the value of parameters changes with temperature, and then studies the relationship between typical characteristics of TSEP and temperature. The research aims at analyzing the temperature sensitivity of TSEP, providing a temperature measurement method of estimating accurately junction temperature of IGBT. The experimental results show that the junction estimation method based on typical characteristics of TSEP is feasible.