This paper presents a numerical simulation for the behavior of volatile organic compound(VOC) from building material and their diffusion in various slot ventilated room by a computational fluid dynamics. A polypropylene styrene-butadiene rubber(SBR) floor plate is chosen as the emission source of VOC. This study investigates spatial concentration distributions and time history of room-averaged VOC concentration for four ventilation systems. The results of this study shows that for ten-days calculation room averaged VOC concentrations for four cases are quite different. And the results indicate that displacement ventilation system are more effective to remove VOC in a room than mixing ventilation system.