An investigation of radiated reliability of HBT and MOSFET which fabricated on 0.35 μm SiGe BiCMOS technology is presented under dose rates of 500 mGy(Si)/s and 1 mGy(Si)/s with a 60Co γ irradiation source. Gummel characteristics of SiGe HBT and transfer characteristics of MOSFET are measured before and after irradiation. Base current (IB), leakage current (IOFF) and threshold voltage (VTH) are extracted from gummel and transfer characteristics. Our results show that there is a slight increase in IB and an observed decrease in β for SiGe HBT device. For NMOS transistor, a conspicuous increase in IOFF and slight drift in vtH. No dose-rate effect has been seen in SiGe HBT devices; however, it has been observed in NMOS transistors.