In this study, a new method is proposed to evaluate the amount of adhered fuel when fuel spray impinges on a wall surface, by considering the normal and tangential droplet impact velocities. To verify this method, how the amount of fuel adhering to a flat plate varies with the spray's angle of incidence is examined. Our experimental results show that less fuel adheres to the wall when spray is oriented obliquely. To verify our method, the concentration of the air-fuel mixture and the fuel film thickness formed in an engine intake port model are also examined. By comparing these experimental results with our calculated results, it is shown that the proposed method can evaluate the behavior of adhered fuel, which conventional methods cannot evaluate.