In This study , the large amplitude vibration analysis of laminated composite beam under thermal stress with axially fixed ends is investigated with symmetric and asymmetric layup orientations by using the Rayleigh–Ritz (R–R) method. An exhaustive set of beam boundary condition are studied, namely, hinged-hinged, clamped-clamped, hinged- clamped, hinged-guided and clamped-guided beam in order to prove the efficacy of the present formulation. The composite beam is studied in this paper based on Euler-Bernoulli assumption together with von-Karman’s strain-displacement relation. The simple and efficient closed-form solutions are obtained for the nonlinear harmonic radian frequency as function of central amplitude of the beam using the R–R method. Comparison between results of the present study and those available in literature shows the accuracy of presented closed-form solutions.