This paper is devoted to investigating the dynamic mechanical behavior of composite shells composed of modern Functionally Graded Materials (FGMs) using the Continuous Element Method (CEM). The study focuses on analyzing submarine-like composite shell configurations, comprising cylindrical shells, conical shells, and inner/outer ring stiffeners constructed from FG materials. The natural frequencies of these structures are evaluated considering the diverse mechanical properties of FG materials, including coefficients a, b, c, and various exponent values (p). The findings demonstrate the superiority of CEM in terms of computational efficiency and accuracy, even at high frequencies.