Abstract: Cylindrical shell is widely adopted in the field of maritime industry. Cracks are frequently occurred due to the external forces such as impact, corrosion and alternate load, so that research on the dynamic characteristic of cylindrical shell with cracks is evidently of interest to design work. In this paper, the input power flow characteristics of infinite cylindrical shells with circumferential axissymmetric surface cracks are focused. The vibration of the shell is described by FlUgge＇s shell equation. The crack is modeled as line spring. In consideration of the three states of crack, the local compliance matrix at the cracked region is deduuced by using the fracture mechanics. The axisymmetric vibration and wave propagation of the cracked shell is analyzed under the excitation of the linedistributed force. The relationships between the input power flow and the crack parameters along with the shell parameters are discussed. The results demonstrate that the presence of crack changes the power flow characteristics. The power flow is close related to the location and depth of the crack.