In order to identify effects of staggered blades on cavitation characteristics of double-suction centrifugal pump, considering the influence of the shrouds of pump and fillet, the blades of both sides of the impeller were separated circumferentially at 0°,10°,15°,20° and 30° staggered angles, respectively. RNG k-ε turbulence model and Rayleigh-Plesset equation were applied to simulate cavitation characteristics and performance test under design conditions. In order to highlight the generality of the research conclusion, the definition of staggered degree was introduced and the vapor volume fraction on the middle stream surface of impeller and head and the variation of the impeller torque at different staggered degrees were analyzed. Compared with experimental values, the results indicated that the prediction results were accurate to some extent;it can be seen that the selection of reasonable staggered degree can improve the performance of anti-cavitation. At different staggered degrees, the corresponding net positive suction head values were different when the impeller torque was subjected to a sharp decrease, when the staggered degree was at 1, the impeller torque was stable in cavitation and relatively less in cavitation;when net positive suction head was under critical net positive suction head, the region of static pressure was lower than the local cavitation pressure at the double-suction centrifugal pump impeller channel and the vapor occupied the least flow area at the flow channel, staggered degree at 1 was the least. Therefore, the cavitation characteristics were relatively good when the staggered degree was at 1 to provide a theoretical basis for improving the cavitation characteristics and the safe operation of double-suction centrifugal pump.