According to one embodiment, a system is disclosed, which uses road parameters defining the road network and model parameters used as initial-value parameters, thereby performing traffic simulation by the microsimulation method. The system includes a traffic simulator and a display controller. The traffic simulator performs traffic simulation to predict a traffic condition on an object road of a road network. The display controller controls a display unit, displaying the result of the simulation. More precisely, the display controller displays a dynamic image showing the traffic condition of vehicles running on the road network, on the screen of the display unit, and changes the image in terms of pattern, in accordance with a display instruction.