<p>This research surveys the flutter instability and vibration analysis of hybrid laminated composite truncated conical shells subjected to fluid flow. The study explores the effect of the presence of a viscous fluid on the frequency of the cone and its velocity in inducing flutter and divergence instability. The simultaneous combination of several controlling parameters, including fluid velocity, layering configuration, and the number of layers, aids in adjusting the natural frequency of the system to the optimal condition. In this study, a third-order shear displacement field assumption is utilized, and the fluid force is applied as external work using a linear stress–strain relationship, with governing equations derived from Hamilton’s principle. The extracted equations are converted into discrete equations for numerical solution using a systematic differential quadrature method employing the Kronecker delta function. To calculate the properties of graphene, the Halpin–Tsai model is used, while the rule of mixtures is applied to estimate the mechanical properties of carbon nanotubes. The validation of the results is conducted in cases involving a cylinder containing fluid. The impact of parameters such as radius, various arrangements of nanotubes and graphene in thickness, weight percentage of nanotubes, fluid velocity, and viscosity on the issue is also examined. In the fluid analysis, the results indicate that as the fluid velocity increases, the natural frequency decreases, and at critical velocity, the phenomenon of divergence occurs. This point marks the onset of the interweaving of vibrational modes, leading to the flutter phenomenon. The extent of the impact of each parameter is detailed in the results section.</p>