Abstract: The present invention discloses a method for measuring an actual temperature of a flame by using all information of a radiation spectrum and a measurement system thereof. The method includes: conducting more theoretical data processing by using energy level structure correction, wherein all information of the radiation spectrum can be used; and by way of a keyboard input manner or a data transmission input manner, acquiring an energy level structure correction parameter, and finally acquiring a more accurate actual temperature value of a measured flame. The method effectively overcomes a defect that the true temperature of the flame can be obtained by only conducting radiance correction through data processing with great calculations when adpted multi-spectral temperature measurement method.