The three-dimensional turbulent flow in a vertical axial-flow pumping system with cube-type intake passage was simulated based on Navier-Stokes solver embedded with RNG k-∊ turbulence model. The internal flow pattern of the cube-type intake passage and the vorticity distribution around the bell-mouth of flare tube were analyzed. Four types of antisubmerged vortex devices were designed based on the vortex tubes intensity conservation theorem. The high-speed photography was applied to observe the flow pattern of the cube-type intake passage with 4 types of vortex-elimination devices. The predicted trajectory of submerged vortex was validated by the comparison with the tested results by PIV (particle image velocimetry). The results show that, with the increase of flowrate coefficient K Q, the maximum vorticity magnitude of every measuring line increases gradually and the increased amplitude of maximum vorticity magnitude decreases gradually. When a submerged vortex flows from the bottom of the cube-type intake passage into the flare tube, the position of maximum vorticity is closer to the center point of the bell-mouth than the initial position. Strong submerged vortex can be successfully suppressed by vortex-elimination device installation on the bottom of cube-type intake passage just below the bell mouth.