Abstract: Based on the design parameters and field test data of a supercritical opposed combustion boiler in a power plant, this paper uses ANSYS Fluent software to conduct numerical simulation research on the low-load operating state.According to the actual situation of the field test, the boundary conditions such as the operation mode of the burner, wind speed and air volume are controlled, and the simulation results directly reflect the combustion state in the furnace. After verifying the accuracy of the model, the calculation results of the 25% and 30% load conditions are further compared.The results show that the temperature field and velocity field are uniform and symmetrical under the 25% load condition,and the overall stable combustion performance is better than that of the 30% load condition. condition. In the 30% load condition, due to the more middle-level burners in the rear wall, the hedging performance is poor, which not only easily causes the overheating of the front wall water wall, but also produces more NO_x accumulation in the front wall, and the outlet NO_x emission in the 30% load condition The amount is about 1.35 times of the 25% load condition.