Disclosed is a bandgap reference voltage generator insensitive to changes of process, voltage, and temperature. A bandgap reference voltage generator may detect current having characteristic of CTAT and current having characteristic of PTAT which flow in a current compensation part included in an amplification part, and provide body voltage to one of two input transistors included in the amplification part in response to ratio of the two currents when the ratio is different from the preconfigured reference value. Thus, characteristics according to changes of parameters of elements and change of offset of the amplification part due to changes of PVT may be enhanced, and a characteristic of power supply rejection ratio (PSRR) may be enhanced.