Distribution uniformity (DU) and Christiansen uniformity coefficient (CU) are two important indicators for evaluating the hydrodynamic performance and irrigationg quality of sprinkler irrigation system. In order to research the impact of the pressure, sprinkler combinations and interpolation methods on the distribution uniformity and Christiansen uniformity coefficient, CU and DU were computed by linear interpolation, cubic interpolation, cubic spline twice interpolation, inverse distance weighting method and plane interpolation method with two combinations (rectangular and regular triangle), and 1m sampling space. Using the experimental data of FY RB-471 sprinklers without wind simulated the water distribution under different pressures. The results showed that CU calculated form rectangular combination date were less than form regular triangle combination date by 1.56%~4.77%. Similarly, DU calculated form rectangular combination date were less than form regular triangle combination date by 4.26%~9.19%. Different interpolation methods for the calculation results of CU and DU are not obvious, while the pressure is an important factor for affecting the sprinkler uniformity.