The engineering analysis method for vortex-induced transverse vibration of submerged floating tunnel (SFT) tether is presented, based on the modified wake oscillator model. The effects of specific gravity ratio and shear current character on vortex-induced vibration of tether are investigated. The calculated results show that the distribution of lock-in regions and the vortex-induced vibration of tether vary with the specific gravity ratio of SFT. The increase of shear parameter makes the amplitude of vortex-induced vibration decrease. Furthermore, if shear current is replaced by uniform current to calculate the vortex-induced vibration of tether, its response amplitude may be overestimated.