The water distribution under the condition of combined sprinklers can be calculated using the combination of cubic spline and double interpolation superposition method and the water distribution of a single sprinkler. This study aims to verify the applicability of this method and investigate the changes of sprinkler irrigation uniformity with variable spacing between sprinklers and laterals. Through field experiments, the water distribution of a ZY-2 type sprinkler and the 18 m×18 m combination mode was measured, and the corresponding water distribution uniformity was calculated. A numerical simulation model was developed using MATLAB to calculate water distribution and irrigation uniformity under the condition of different sprinkler combinations. The results show that the relative error and RMSE of simulated and measured sprinkler irrigation depth are 8.49% and 3.17 mm, respectively, and the relative error of the irrigation uniformity for the combined sprinkler mode is 1.85%. This indicates that the model can accurately simulate the water distribution and irrigation uniformity under different sprinkler combinations. The simulation results show that sprinkler combination mode of 21 m×21 m for the ZY-2 sprinklers has the highest irrigation uniformity (0.873). Increasing the spacing of sprinklers and laterals can reduce the sprinkler irrigation uniformity; however, the uniformity decreases more when the nozzle spacing increases. The research results are expected to provide technical support for optimizing the layout of sprinklers.