Emissions of underground diesel engines are facing more and more stringent control because of their adverse effects on human body. The novel zonal guarantee technology presented in this paper will remove the heat and contaminant simultaneously and effectively. The technology divides the space into the stronger load zone and the weaker load zone. For different zone, ventilation and cooling system uses different strategies to remove the heat and contaminant. In the end, the novel technology is applied to an underground generator plant in Hangzhou (China). The CFD simulation results show that the different location combinations of the fume exactor and exhaust duct may affect the efficiency of removing the CO, there is an optimal location to controlling the CO in the underground diesel generator plant.