Insulated gate bipolar transistor (IGBT) junction temperature estimation is critical for lifetime prediction. However, most traditional temperature evaluation methods need a set of testing equipment corresponding to an IGBT chip. In this article, an online bridge-level junction temperature evaluation method via the induced voltage undershoot between Kelvin and power emitters of lower IGBT for junction temperatures extraction of two IGBTs in half-bridge is presented. The v_eE undershoot of lower IGBT during turn-off transient has a good linear relationship and high relative sensitivity for estimating temperatures of upper and lower IGBTs. So that, the bridge-level junction temperature monitoring method can be implemented online in converters with no disruption to operation. Double-pulse and three-phase inverter are established and the experimental results reveal the relation between T_j of IGBT and v_eE undershoot under different working conditions. It can be concluded that the v_eE undershoot is a potentially practical TSEP for online bridge-level IGBT temperature evaluation.