This paper model the EV charging market, treating EVs and stations as players. Our findings indicate that the Nash equilibrium does not accurately reflect the real-world competition among charging stations. This discrepancy arises because the decision-making processes of EVs and charging stations are not simultaneous. In this paper, we model this hierarchical decision-making process as a Stackelberg game, where charging stations act as leaders and EVs as followers. We further demonstrate that, under certain conditions, the Stackelberg equilibrium not only exists but is also unique. To validate our model, we use EV charging data from the Sydney city road network to examine how changes in charging prices impact EV flows. The results show the dynamic interaction between EVs and charging stations, highlighting the balancing effect of charging queues and price variations.