The present investigation deals with the post buckling analysis of the moderately thick angle-ply laminated composite rectangular plates under in-plane uniform temperature induced loading. von Karman type geometrical nonlinearity and first order shear deformation theory are employed in the formulation of the problem. Nonlinear governing differential equa- tions of equilibrium are linearized by quadratic extrapolation technique and resulting linear differential equations are solved iteratively, using Chebyshev polynomials. The boundary con- ditions consisting of clamped. simply supported and their combinations are considered. An incremental iterative approach is employed to estimate the critical/buckling temperatures. The effects of b/a, a/h, boundary conditions, Iamination scheme, Young’s moduli ratio and ratio of coefficients of thermal expansion on post buckling behaviour are investigated. The present investigation procedural with the post buckling analysis of the moderately thick angle-ply laminated composite rectangular plates under-plane uniform temperature induced loading. Von Karman type geometrical nonlinearity and first order shear deformation theory are employed in the formulation of the problem. governing differential equa- tions of equilibrium are linearized by quadratic extrapolation technique and resulting linear differential equations are obtained iteratively, using Chebyshev polynomials. The boundary con- ditions consisting of clamped. simply supported and their combinations are considered. An incremental iterative approach is employed to estimate the critical / buckling temperatures. The effects of b / a, a / h, boundary conditions, Iamination scheme, Young’s moduli ratio and ratio of coefficients of thermal expansion on post buckling behavior are investigated.