The invention discloses a parallel reactor electrode calibration device and parallel calibration method, wherein the device comprises a tank body, a tank cover, a gas intake pipeline, a gas exhaust pipeline, a stirring mechanism, a temperature electrode and/or a standard thermometer, a temperature adjusting mechanism and a calibration mechanism; the tank body contains a to-be-measured liquid; thetank cover covers the tank body and is provided with a plurality of connecting and inserting ports, and to-be-measured electrodes are inserted in the connecting and inserting ports; the gas intake pipeline and the gas exhaust pipeline are mounted on the tank body or the tank cover, and the gas intake pipeline and the gas exhaust pipeline and/or the tank body and the tank cover are provided with apressure detection device and a gas adjusting valve; the stirring mechanism acts on the liquid in the tank body and makes the liquid mixed evenly; the temperature electrode and/or the standard thermometer are inserted in the connecting and inserting ports of the tank cover so as to measure the temperature of the to-be-measured liquid; the temperature adjusting mechanism is used for heating and cooling of the tank body liquid; the calibration mechanism is in communication connection with a measurement and control system for synchronous calibration of the to-be-measured electrodes. The tank cover is designed with the connecting and inserting ports for inserting the to-be-measured electrodes, the stirring mechanism can stir the to-be-measured liquid in the tank body to make the internal physical and chemical parameters even, and multiple electrodes are calibrated in the same to-be-measured liquid environment at the same time.