The invention relates to a two-stage buffer with a temperature protection function. The two-stage buffer is composed of a first-stage buffer and a last-stage buffer; each of the first-stage buffer and the last-stage buffer comprises a circular tube and a cylinder, a cylinder cover is hermetically arranged at the open end of the cylinder body, a piston rod is arranged in a central through hole of the cylinder cover in hermetical running fit manner, and a piston body component is arranged at the right end of the piston rod, is suitable for performing piston motion in the cylinder body and is in running seal fit with the inner wall of the cylinder body; the cylinder of the first-stage buffer forms the piston rod of the tail-stage buffer; temperature sensors are arranged on right end faces of the piston rod components of the first-stage buffer and the last-stage buffer, the temperature sensors include temperature sensors suitable for detecting medium temperature, and the temperature sensors are connected with a PLC (programmable logic controller); Nixie tubes are arranged on the outer cylindrical wall of the two-stage buffer, and the PLC is suitable for displaying the medium temperature through the Nixie tubes.