The invention relates to a boiler heating surface wall temperature protection method and device. The method comprises the following steps that 1, historical combustion adjusting working conditions areclustered, and the combustion adjusting working conditions are divided into a plurality of groups of different combustion working conditions; 2, for each combustion working condition, a machine learning model of the risk coefficient of the heating surface is established, and a heating surface risk coefficient model library is formed; 3, based on a combustion working condition and a heating surface risk coefficient model library, the optimal energy flow distribution of the heated surface of the current real-time working condition is optimized, and the optimal energy flow distribution of the heating surface is obtained; and 4, soot blowers in different areas can be adjusted according to the optimal energy flow distribution of the heating surface, and the soot blowing strength in different areas can be adjusted, so that the energy flow distribution of the heating surface can be optimized, and a protection strategy for the wall temperature of a boiler steam-water pipeline can be obtained.The method is based on energy flow clustering and distribution soot blowing, starting from the historical operation data of the site, and on the basis that the boundary conditions of the combustion system are fixed, the soot blowing force in different areas is adjusted so as to optimize the energy flow distribution of the heating surface, and a protection strategy for the wall temperature of theboiler steam-water pipeline is obtained.