Silicon-Germanium Heterojunction Bipolar Transistors(SiGe HBTs) is a strong contender for space applications in extreme environment on account of its superior temperature characteristics, which can bear extreme temperatures from -180 ℃ to 200 ℃ owing to the bandgap grading of heterojunction. Because of new features in material, structure and process, the radiation effects of SiGe HBTs present complex characteristics which are different from those of bulk-Si devices. In this work, the research dynamics and trends of space radiation effects in SiGe HBTs are introduced, and the radiation effects of domestic SiGe HBTs include Single Event Effects(SEE), Total Ionizing Dose(TID) effect, Enhanced Low Dose Rate Sensitivity(ELDRS) and synergistic effect are highlighted. The research shows that SiGe HBT naturally presents favorable build-in TID and displacement damage hardness without any radiation hardening, but the high sensitivity to SEE is a main drawback. Due to the different manufacturing processes, the domestic SiGe HBTs experience significant low dose rate sensitivity and are vulnerable to combined effect of ionizing dose/displacement damage and total ionizing dose on single event effect.