The constant injection mass is a criterion for measuring the thermal efficiency of diesel engines. In this study, the effects of the injection pressure on the ignition and combustion characteristics of an impinging diesel spray are investigated for a constant injection mass. Experiments are performed in a constant volume combustion chamber including a high-pressure common-rail injector with a single-hole nozzle. A high-speed camera is used to capture the ignition and combustion behavior. Variation laws for the ignition delay, ignition location, combustion duration, flame area, spatially integrated natural luminosity, and time integrated natural luminosity are obtained by analyzing the images captured in these experiments.