On the basis of analyzing the relationship between pressure before the nozzle and nozzle area, radius of throw, a new type of variable-rate sprinkler was developed by using activity pieces and non-circle nozzle device on an impact sprinkler. The structure and working principles were presented. Experiment of hydraulic performances was conducted and analyzed. The water distribution isoline of single nozzle was plotted by using Matlab. Results showed that the variable-rate sprinkler with non-circle nozzle was able to operate reliably, and the triangle wetted area and square wetted area was obtained. Compared with the traditional variable-rate sprinkler, the variable-rate sprinkler with non-circle nozzle has better hydraulic performance and the spray uniformity is improved.