The simulation model electronic unit pump (EUP) was established in AMESim environment. The accuracy of the model was validated by comparing with the experiment results. By simulating, the influence of cam profile velocity, plunger diameter, length of high pressure fuel pipe, inner diameter of high pressure fuel pipe on injection pressure, cycle fuel injection quantity, fuel injection duration and coefficient of fuel feeding was revealed. By using the design of experiments (DOE) method, and taking the interaction into consideration, correlation between various factors and injection characteristic was analyzed. The correlation coefficient was obtained by analysis, the results show that not only the single factor but also the interaction factor of various influence parameters has correlation with the injection characteristic, and the correlation coefficient represents complex law with the speed variation.