Design scheme of steel shell flow tube in the inflow and outflow passage of the vertical axial pumping stations takes advantages of conventional concrete scheme in simple construction and convenient installation of the pump. A three-dimensional pumping station model was established based on fluid-structureinteraction method in ADINA. Typical measure points were selected to analyze the features of the unsteady turbulent flow in fluid zone and vibration responses of the steel shell tube in solid zone. Time and frequency domain investigation of fluid domain revealed the transmission path of pressure pulsation, that was the pulsation transferred from the pump to the inlet and outlet respectively with amplitudes sharply decreasing, which verified the rationality of calculation and established the basis on structure analysis. Dynamic displacement, velocity andacceleration analysis of measure points in steel shell tube showed that top shell domain near the inlet of steel shell flow tube had obvious vibration amplitude, which required great attention. The first main frequency equaled the rotational frequency of the blade, indicating one of the most important vibration sources in the pump was the pressure pulsation induced by blade rotation. The design scheme of steel shell flow tube is practical and could be promoted to other similar pumping stations because the vibration amplitude is much lower than theregularity. This research provides great importance to the design and application of the steel shell flow tube in pumping stations.