In this paper we establish a three-dimensional (3D) numerical simulation model of domestic SiGe heterojunction bipolar transistor (SiGe HBT) by using technology computer aided design tools, to study the bias effect on single event effect (SEE) of SiGe HBT. The response relationship between SEE and the bias of SiGe HBT is identified based on the analyses of transient current peak and charge collection of each terminal. The results show that the worst biases for SEE are different for different terminals. Even for the same terminal, the worst biases for charge collection and transient current peak are different. This phenomenon is caused mainly by the influence of applied electric field and the change of carrier transport mode.