The invention belongs to the technical field of electronic circuits and particularly relates to a voltage reference circuit with a characteristic of ultralow power consumption. According to a rough voltage reference, a voltage hardly varying along with the temperature is obtained to serve as a gate voltage of an NMOS (n-channel metal oxide semiconductor) tube, operation in a linear resistance areain a whole temperature range can be realized, and a megohm-level resistor can be replaced; by a voltage subtraction module for outputting the voltage reference, a final voltage reference temperaturecoefficient of reduced through selection of field effect transistor structural parameters. The resistor-free ultralow-power-consumption voltage reference circuit available for 0.45V operation is capable of operating under a low power voltage while power consumption is only several nanowatts, use of any types of bipolar transistors and high-resistance resistors is avoided, a standard full CMOS (complementary metal oxide semiconductor) process can be adopted for manufacturing an integrated circuit, and an application range and flexibility are remarkably improved.