Abstract: In order to clarify the hydraulic characteristics of the bidirectional vertical axial flow pump device of the Weicun Hub Expansion and Reconstruction Project Pumping Station,the structural characteristics of bidirectional vertical pump device and bidirectional shaft tubular pump device are compared and analyzed from the aspects of pump device efficiency,unit equipment installation,maintenance and reliability,and the bidirectional vertical pump device is optimized. In order to further clarify the hydraulic characteristics of the bidirectional vertical axial flow pump device,the tests on the energy performance,cavitation performance and flight performance of the pump device model are carried out. The results show that when the blade placement angle is-8°～+4°,the maximum efficiency of the pump device is 74.26%,and the blade placement angle is-6° and the pump device head is 3.981 m;in the range of 2.72～5.25 m,the model pump device runs stably without obvious adverse noise and vibration. When the maximum head is 5.25 m and the blade placement angle is +2°,the submerged depth of the pump meets the requirement of the maximum required cavitation amount of 9.35 m,which meets the requirement of the installation of the submerged depth of the pump. When the blade placement angle is-8°,the prototype pump has a runaway speed of 1.705 times its rated speed. The hydraulic loss of bidirectional outlet conduit is the main factor affecting the hydraulic efficiency of such pump devices.