Recently, in order to improve the thermal efficiency of diesel engines, there has been a tendency to increase injection pressure of diesel fuel to promote atomization of the fuel. Moreover, the combustion chamber of the engine has been downsized to reduce fuel consumption. These strategies for the improvement of thermal efficiency result in impingement of the diesel spray on a cavity wall of the combustion chamber. Therefore, it is necessary to understand the impingement process of the diesel spray in order to consider reduction strategy of heat loss by heat transfer between the impingement spray and the cavity wall. Moreover, ambient gas density in a combustion chamber of a modern engine tends to increase by a high boost as compared with a conventional engine in order to apply an exhaust gas recirculation (EGR) system. In this study, the effects of ambient gas density and injection pressure on flow characteristics of the impingement diesel spray were investigated. The velocity field of the impingement diesel spray was measured with time-resolved PIV, and the mean velocity field and turbulent kinetic energy inside the impingement spray were evaluated. As a result, there was not much difference in normalized velocity distributions in the wall spray flow region, even though ambient gas density and injection pressure were changed. The normalized velocity distributions of the spray were compared with those of impingement air jets obtained from the existing literature. The velocity distribution of the spray was similar to that of the impingement air jet. It means that the analogy between the spray and the jet might be maintained, even though there was a difference between single-phase flow and two-phase flow. Moreover, turbulent kinetic energy of the impingement spray near the wall decreased with a raise of ambient gas density and with a decrease in injection pressure.