Abstract: The submerged cylindrical shell reinforced by supports of ring and bulkhead is the primary structure of submarine, torpedo and submerged vehicles, however the study on the characteristics of the structure-borne sound has been received much attention. Based on Flügge shell equations and Helmholtz equation, the influences of rings and bulkheads with variable parameters on the input power flow of excited vibration of submerged cylin ndrical shell are investigated by space harmonic analysis. Four external forces and moments of rings, bulkheads applied to the cylindrical shell are considered respectively. Analytical formulas of input power flow of the cylindrical shell subjected to the harmonic forces are derived. The work can be provided as a reference for the engineering application.