An air conditioning system includes an air conditioner for blowing conditioned air toward a compartment of a vehicle, and a dashboard having a design surface exposed to the compartment. An inner air passage extending nearly parallel to the design surface is formed in the dashboard, and a plurality of diffusion blowing openings are formed in the design surface. Thus, the condensed air is blown from the diffusion blowing openings into the compartment of the vehicle, while passing through the inner air passage. For example, cool air is blown from the diffusion blowing openings, so that the cool air can cool the dashboard while cooling the compartment of the vehicle. Moreover, because the cool air passes through the inner air passage extending nearly parallel to the design surface, the dashboard can be effectively cooled.