To explore the effect of rotational speed of sprinkler on hydraulic performance,10 different viscosities damping oil were set to adjust the rotational speed based on the Nelson R33 sprinkler.The results indicated that the viscosity of damping oil could significantly change the rotational speed of the sprinkler.Under the pressures of 150 and 200kPa,the rotational speed ranged from 0.085 to 0.26r/min without damping oil while the rotational speed ranged from 202 to 229.59r/min with the maximum viscosity oil of KL704.The sprinkler range decreased greatly with the increase of rotational speed under the rotational speed below 20r/min,whose decreasing amplitude ranged from 25%to 26.9%,while the sprinkler range tended to change stably with the rotational speed above 20r/min.Considering the effects of rotation speed on sprinkler range and sprinkler irrigation uniformity comprehensively,it was more conducive to the combined sprinkler irrigation uniformity and the economy of system arrangement that the rotational speed was about 1r/min under pressures of 150~200kPa.