The invention discloses a quantitative temperature identification method for a discharge channel based on a schlieren instrument. The method comprises that temperature data of an infrared image of the discharge channel is obtained; and temperature of the discharge channel is obtained according to a standard temperature transfer function curve and the temperature data of the infrared image of the discharge channel. An infrared camera shoots infrared images of blackbodies of at least two temperature calibrating points, and the standard temperature transfer function curve is determined according to the infrared images of the blackbodies of the at least two temperature calibrating points. A quantitative temperature identification device based on the schlieren instrument and the infrared blackbodies comprises a light source, a slit, a main reflector, a flow field, an auxiliary reflector, the blackbodies and the infrared camera. On the basis of traditional schlieren instrument technologies, temperature data of the discharge channel is read directly, interference of artificial factors is eliminated, data can be traced back, and the parameter obtaining accuracy in the discharge process is improved.