Purpose <p>The paper proposes a hybrid analytic-numerical approach for the vibro-acoustic analysis of a combined shell with interior substructures.</p> Methods <p>Based on the Flügge shell theory, the dynamic model for both shell segments is derived using the first-order differential control equation. Considering the boundary and continuous conditions, the entire dynamic governing equations of the combined shell with bulkhead are assembled by the Precise Transfer Matrix Method (PTMM), while the interior substructure is modeled using the finite element method (FEM). The coupling relations between the substructure and the combined shell are solved to obtain the vibration response by the condensed transfer function (CTF). The acoustic response of the complex elastic structure is obtained by brought into the modified wave superposition method (MWSM).</p> Results <p>The results including vibration acceleration and sound pressure obtained from the hybrid analytic-numerical approach, are compared with those from FEM/BEM and experimental tests, which verify the reliability and applicability of the present approach.</p> Conclusion <p>The hybrid approach proposed in this paper combines the advantages of both numerical and analytical methods, overcoming the geometric complexity limitations of the analytical method and make it possible to deal with more complex structures. When the parameters of the shell or interior structure change, only the corresponding calculation models need to be updated individually, resulting in faster processing efficiency.</p>