Abstract: In order to solve the problems of insufficient air supply,uneven air distribution,intensified air leakage and increased air resistance in deep shaft and roadway below a certain height of 200 m in Guangxi,the modeling and optimization design of ventilation network of the deep mine were carried out by using Ventsim 3d ventilation simulation system,a professional ventilation software.The ventilation network was calculated in the most difficult period of mine ventilation.By means of establishing new ventilation roadway,replacing main fan parameters,and adding local fan,the efficiency of the main fan reached 80.1%,and the air flow in each shaft reached the design requirements,which provided data support for the actual ventilation design.