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Two-direction tubular pump device can be adopted to meet the drainage and water transfer, so it was often used along Yangtze River and sea area. The analysis of hydraulic performance and internal flow becomes research hotspot. The twodirection tubular pump device consists of inlet flow passage, two-direction impeller, straight blade guide vane and outlet flow passage. In order to analyze the effect of guide vane position on hydraulic performance and flow pattern, the CFX14.5 was used to obtain the steady flow field in pump device of six different guide vane positions under positive and reverse conditions. The SST model was chosen, and mass flow rate and total pressure were set at inlet and outlet, respectively. The interfaces between inlet flow passage and impeller, and between impeller and guide vane were set as “Frozen Rotor”. The interface between guide vane and outlet flow passage was set as “None”. In addition, a smooth wall condition was used for the wall function. The results showed that good agreements between simulated and experimental results can be obtained, and the maximum relative error was less than 5%. Under positive rotation, for part-load condition, the efficiency was declined with the increase of guide vane position S and the maximum loss value in diffuser passage can be observed when S was 40mm. However, for over-load condition and design condition, the efficiency was increased with the increase of S and the minimum loss value in diffuser passage can be obtained when S was 100 mm.Under negative rotation, the effect of guide vane position on hydraulic performance was not obvious. In summary, the guide vane position S with value of 100mm was optimal. The results can provide reference opinion for two-direction tubular pump device.