The invention provides a method for measuring a flame temperature measurement system of a double-optical-path optical structure, which relates to the technical field of measurement. One beam of radiation light emitted by the flame is divided into two beams of light splitting, and the two beams of splitting light are combined respectively through a red filtering piece and a green filtering piece.A CCD camera is used for shooting a radiation picture and transmitting the radiation picture to a computer, and the computer carries out filtering processing on the radiation picture, the green and red primary colors are separated. A flame temperature field is obtained through calculation by utilizing a double-color method temperature measurement principle formula. According to the invention, thetechnical problem that a single CCD camera double-color method is large in temperature measurement error in the prior art is solved. The invention is advantageous in that the double-optical-path optical structure simultaneously obtains the combustion conditions of the flame transient state in the two narrow band-pass ranges, the two paths of light rays are combined into one path, and the error caused by the fact that the two paths of radiation light rays are separated and received at the later stage of image radiation point position matching is avoided; the transient performance of flame burning is considered; the dual-optical-path optical structure can obtain a narrow-band-pass monochromatic radiation image, and conforms to the assumption of wavelength fixation in the double-color-methodtemperature measurement principle.