Stiffened plates are used in several applications, such as aircrafts, ships and aerospace structures. Geometric nonlinearity and stability analyses of stiffened and unstiffened composite laminated plate are presented in this paper using the high order finite element. Strain energy method has been used in the derivation. The strain energy has been divided into infinitesimal strain energy for small deformation and finite strain energy fro large deformation. The shear effect has been taken into consideration in the element derivation. The coupling effect of small and large deformation on the strain energy has been introduced to define the finite force vector. The results of the proposed element derivation have been validated through the comparison with published, software (ANSYS-12) and experimental results with geometric nonlinearity and stability analyses. Parametric investigations have been carried out on different case studies with different boundary conditions, number of layers, stacking sequence and aspect ratio.