Diesel fuel injection play an important role in fuel combustion, so it has directly impact on engine thermal efficiency, mechanical load and thermal load as well as exhaust and noise. In this paper a pressure transducer which was clapped on the high pressure line was used to measure the fuel pressure in the high pressure line. In processing and analyzing the pressure signals, the advanced fuel delivery angle, fuel injecting pressure and fuel injecting duration were calculated. This method realizes indirectly monitoring the performance of diesel fuel injection.