Abstract: Abstract: Roll wheel line move sprinkling irrigation machine is a kind of important sprinkler irrigation equipment and it is one of the suitable systems for large area of the north China management pattern and level of productivity. However, the hydraulic performance of roll wheel line move sprinkling irrigation machine, which are put into use currently, is poor, limiting the development of roll wheel line move sprinkling irrigation machine. In order to solve these problems, the spray heads of roll wheel line move sprinkling irrigation machine were selected, and the optimal combination of the structure and working parameters of roll wheel line move sprinkling irrigation machine were investigated. Six kinds of popular spray heads including 30PS type, 2000S type, DY-1 type, ZY-2 type, FPY-1 type and 8034D type were used. Then the single spray head hydraulic performance tests were conducted. The test spray heads were mounted vertically on the car of 1-m height, rain gauges were arranged radically with 6 rows and centered on the spray head. During the test, the time taken for each revolution of the spray head and the water depth in the rain gauges were recorded. The spray stability, radial water distribution and rectangular combination sprinkler irrigation uniformity were determined. The suitable sprinkler head for GYP-300 type roll wheel line move sprinkling irrigation machine was chosen. The results showed that the 8034D type spray head had the advantages of high spraying stability, and well combination sprinkler irrigation performance, improving the hydraulic performance of roll wheel line move sprinkling irrigation machine fundamentally. At the same time, the method of 3 factors 5 levels quadratic regression orthogonal rotation center combined was applied to find the optimum parameters combination of roll wheel line move sprinkling irrigation machine. Working pressure of 8034D type spray head, spray head spacing, and spraying distance were selected as the influencing factors, and irrigation uniformity and application intensity were selected as the objective functions. The results showed that the contribution rate on irrigation uniformity was highest for the spraying distance, followed by working pressure and spray head spacing. The contribution rate on irrigation intensity was highest for the spraying distance, followed by spray head spacing and working pressure. The optimum parameter combination that could met the design requirements and had high working efficiency was the working pressure of 0.4 MPa, spray head spacing of 12 m, spraying distance of 18 m. In this condition, the irrigation uniformity could reach 0.91 and application intensity could reach 10.43 mm/h. By comparing with the existing 12 m ? 12 m roll wheel line move sprinkling irrigation machine, the numbers moving units per unit area was decreased by 33.3%, the work efficiency was greatly improved and the labor force was reduced. The study can provide valuable information for the further development of roll wheel line move sprinkling irrigation machine.