In-cylinder direct-injected technology provides a flexible and accurate optimization solution for internal combustion engines to reduce emissions and improve fuel efficiency. With increasingly stringent requirements for nitrogen oxides (NOx) and CO2 emissions, the number of injections in a engine combustion cycle has reached 2 to 3 times in gasoline direct injection (GDI) and high pressure common rail (HPCR) diesel engine. Accurate control of both the timing and quantity of injection events is critical for engine performance and emissions, while the dynamic response of the injector spray characteristic is the key factor. In this paper, a test bench was built for monitoring solenoid injector’s dynamic response, using high-speed microphotography and synchronous current collection system. Experimental study on the dynamic response of GDI and HPCR solenoid injectors was carried out. Comparative study shows that, there is a high correlation between the opening and closing delay time of solenoid valve and the solenoid current. the solenoid valve will not open until the current rate reaches to a threshold calve, when it closes, there is a bump in current curve. Based on this, the dynamic characteristics of solenoid valve such as opening delay and closing delay can be obtained. As for HPCR injectors, by monitoring and analysis of the pressure of the injector inlet, injection duration can be further decomposed into opening process, full-open process and closing process. Compared with the GDI injectors, the change of the injection pressure has great influence on the opening delay and closing delay of HPCR injectors, but the actual fuel injection duration is different.