Abstract: Flow induced vibration (FIV) widely exists in shell-and-tube heat exchangers, and the helical tube heat exchangers are applied in various industrial heat exchangers recently due to their compactness in volume and high efficiency in heat transfer. In this paper, FIV analysis was carried out for a single helical tube. The fluid density distribution of primary and secondary sides, the fluid velocity field of primary side, and the corresponding mode shape and natural frequency were calculated by RELAP5 program, CFD analysis code FLUENT and finite volume analysis code ANSYS, respectively. The fluid-elastic instability ratio and RMS ratio of turbulent buffeting were calculated under support numbers of 0, 1, 2, 4 and 8. The results show that the four symmetry supports design can meet the requirement of ASME and TEMA code in avoiding fluid-elastic instability and turbulent buffeting.