Abstract: In order to study flow features of bulk coal and influence factors during coal unloading period,discrete element software analysis pack-EDEM was applied to establish analysis model of mode coal bunker and bulk coal,to state certain methods to establish coal bunker model,coal partical model and bulk coal generation with EDE M. The results showed that coal unloading process would be changed from mass flow steadily to hopper flow. The analysis of unloading coal flow state and velocity influen ce factor was conducted to partical density,bulk coal water content,partical size distribution and bulk coal parameters as well as wall fraction factor,unloading hopper inclina tion,unloading hopper outlet diameter,coal bunker material and structure parameters individually. Among them,the higher water content was,wall fraction coefficient would b e less small and the unloading hopper inclination and outlet diameter would be higher. When coal flow state was close to mass flow,the higher unloading velocity would be f aster. The more larger the partical density and partical diameter was,the faster the unloading velocity would be and would not be affected to coal material flow state obviou sly.