This study investigates the forced vibration response of a porous cylindrical shell resting on a viscoelastic foundation and interacting with a surrounding fluid. The shell kinematics are described using classical shell theory, and the governing equations are derived based on Hamilton’s principle. Fluid-structure interaction is modeled through the velocity potential formulation and the continuity of velocity at the shell-fluid interface. To obtain the dynamic response of the system, the assumed-mode method combined with the Galerkin technique is employed. The results show that the geometric parameters, porous material properties, and viscoelastic foundation characteristics have a pronounced influence on the dynamic behavior of the shell. Increasing the shell thickness and the foundation stiffness and damping coefficients reduces the vibration amplitude. In contrast, a higher porosity fraction leads to an increase in the vibration response due to the reduction in effective stiffness. Moreover, the presence of the fluid significantly modifies the response through added-mass effects. The findings of this work may be useful in the design and optimization of lightweight shell structures for marine, aerospace, and mechanical applications.