The invention discloses a flame three-dimensional temperature distribution reconstruction method based on bi-spectral radiation information. The flame three-dimensional temperature distribution reconstruction method is characterized by comprising the following steps: 1) dividing a flame microelement according to acquired flame bi-spectral radiation information and establishing a flame radiation transfer equation; 2) setting a target function, iteratively updating a flame absorption coefficient according to a reconstruction algorithm and reconstructing a flame three-dimensional temperature field. The flame three-dimensional temperature distribution reconstruction method based on the bi-spectral radiation information, disclosed by the invention, has the benefits that in the iterative solution process of the algorithm, a non-negative least squares algorithm is used, so that the non-negativity of the spectral radiation intensity of each of parts of flame can be guaranteed; the absorption coefficient of each of the parts of the updated flame is also mapped to a set interval, so that the non-negativity of the absorption coefficient is guaranteed; the algorithm has stronger robustness, isindependent of an initial value and can still maintain higher accuracy and better convergence under the situations that inputted data is larger in error, and a random numerical value is set without providing a priori iterative initial value.