Ammonia (NH3),as a hydrogen rich and carbon free fuel,co-combustion with pulverized coal is considered as an effectivemethod to reduce carbon emissions in thermal power plant. However,co-firing NH3 will lead to high emissions of nitrogen oxides(NOx) and poor burnout of pulverized coal. In response to these issues,this study used a two-stage one-dimensional settling furnace toconduct NH3/coal co-combustion experiments,achieving long-term residence of fuel in the high-temperature zone,and exploring theeffects of NH3 co-firing ratio on the characteristics of NH3/coal co-combustion and the emission characteristics of fine particulate matterand NOx. The results indicate that the yield of fine particulate matter first increases and then decreases with the ammonia co-firing ratio,and then increases again,which is consistent with the trend of NOx emissions. NH3 escaping increases with the increase of co-firing ratio.In addition,with the increase of ammonia co-firing ratio,CO emissions exhibits a trend of first decreasing and then increasing. Theunburned carbon content in flying ash decreases with the increase of co-firing ratio,promoting the pulverized coal combustion. The aboveresults are beneficial for further understanding the emission characteristics of pollutants in NH3/coal co-combustion,providing datasupport and theoretical guidance for the development of ammonia/coal co-combustion technology.