This research has been conducted an investigation to the local, distortional and lateral buckling of curved plates based on the Due to the complexity of the closed form solutions for analyzing buckling of cylindrical plates with different boundary conditions, in this thesis the finite strip method was used as a numerical scheme to solve this problem. The assumed curved plate supposed to have simply supported longitudinal edges. The plates may be subjected to a combination of longitudinal and circumferential compressions. In order to calculate the buckling modes and displacements in the plates, sinusoidal functions in the longitudinal direction, and polynomial functions in the circumferential direction have been used. The critical stresses and critical moment of curved plates were obtained by solving an eigenvalue problem. In addition, to analyze buckling of a flat plate, a plate with infinite radius has been assumed and the matrices of stiffness and geometric of the curved plates were modified for flat ones. Further investigations have been done in this thesis including: study of thickness-tapered plates and plates with various curvatures in their cross-section and also study of plates with various circumferential boundary conditions. All these surveys have been conducted in both elastic and inelastic region. Analysis of mixed structures, consist of either flat and curved plate has been another scope of this research. The results of each set of studies have been elaborated distinctly, and the validity of the results has been investigated by comparison with some bench mark problems from literature.