Abstract An analysis on the nonlinear dynamics of a clamped–clamped FGM circular cylindrical shell subjected to an external excitation and uniform temperature change is presented in this paper. Material properties of the constituents are assumed to be temperature-independent and the effective properties of FGM cylindrical shell are graded in thickness direction according to a simple power law function in terms of the volume fractions. Based on the first-order shear deformation shell theory and von Karman type nonlinear strain–displacement relationship, the nonlinear governing equations of motion are derived by using Hamilton’s principle. Galerkin’s method is then utilized to discretize the governing partial equations to a two-degree-of-freedom nonlinear system including the quadratic and cubic nonlinear terms under combined external excitations. Numerical results including the bifurcations, waveform, phase plots and Poincare maps are presented for clamped–clamped FGM cylindrical shells showing the influences of material gradient index, the thickness and the external loading on the nonlinear dynamics.