Abstract: Using coal gangue and iron tailings from a certain area in the middle of Inner Mongolia as the main raw materials and shale as the binder, different specifications of coal gangue and iron tailings fired bricks were prepared. The Effect of coal gangue content, iron tailings content, sintering temperature and sintering time on the compressive strength and water absorption of sintered brick was studied by orthogonal tests. The factors affecting the performance of sintered brick were analyzed by range analysis and variance analysis, and the strength relationship model was fitted. The results show that after optimization, the compressive strength of sintered bricks of different specifications has been increased by 1～3 MPa, and the water absorption has been reduced by 1%～6%. The results of range analysis and variance analysis are consistent. The regression effect of the strength relationship model is significant. The test of leaching toxicity and corrosivity of coal gangue meets the requirements. m (coal gangue)∶m (iron tailings)∶m (shale)=7∶8∶5, sintering temperature 850 ℃, and sintering time 7 h are the theoretical parameters after optimization.