The focus of this research effort was to develop a technique to measure the dynamic responding time of the electronic fuel injector (EFI). Successful implementation of the measurement technique introduced in this paper can be used to evaluate injectors and improve its design. More consistent and precise fuel injectors have the potential to improve fuel efficiency, engine performance, and reduce emissions. According to the dynamic working process of the EFI, the coil current of the EFI can bitterly reflect its dynamic response time, which is the measurement mechanism. Then the test circuits of the opening and closing response time of the EFI were designed, and the measurement system was developed with the C8051F310 as the processor. The results showed that the measurement errors of the opening and closing response time of the EFI were 0.9% and 1.14%, and this met to the testing requirements of some research on the EFI. And so, the measurement system was low cost, convenient and high precision.